GEMINI
MEMORY LIGHTING CONTROL

OPERATOR'S HANDBOOK

Back to contents

CHAPTER 4

DETAILED OPERATIONAL DESCRIPTION

4.1 CONTROL HIERARCHY
The control of any channel in the Gemini memory system is primarily based on a 'Latest-takes-precedence' philosophy, which means that the level of each channel is always determined by the last action which involved that channel. For example, if a channel which is fading up as a result of a fade action is becoming too bright, it may easily be adjusted while the fade is running; the channel is simply selected on the Channel Control keypad and reduced in Level by means of the fader wheel. When the fade is complete, the channel will be at the Level set using the wheel, the later instruction having taken precedence over the earlier.
The above, however, is not true of the Sub-masters, the outputs of which combine with each other and with the system output store on a 'Highest-takes-precedence' basis, subject to the settings of the appropriate master faders. This means that if the same channel is contributed to a Lighting scene by two different Sub-masters, the Level which appears on stage will be that produced by the highest combination of channel and master fader Level. For example, if channel 15 is at Full on Sub-master A and at 50% on Sub-master B, (and both master faders are fully raised, the output level of that channel will be Full. If Sub-master A is now lowered, the channel will dim until 50% is reached, when the Level produced by Sub-master B becomes the higher. To reduce the Level further, both faders must be lowered.

4.2 CHANNEL CONTROL
The Channel Control allows setting and modification of channel levels; either directly onto the system output, or into one of the eight Sub-master stores. Levels may be varied in a continuous manner by the fader wheel (256 discrete steps) or, for rapid setting, they may be keyed in using the '@' button.
In addition to the control of individual channels, groups, previously recorded groups and memories, or combinations of all of these may be selected and controlled.
The keypad and fader wheel may be used to control channels in either the output store, or in any Sub-master store. The required operating mode is selected by means of two buttons, labelled O/P (Output) and SUB (Sub-master) respectively. These are mutually exclusive, either, when operated, illuminating and extinguishing the other. Changing the Channel Control mode from O/P to SUB or vice-versa automatically clears the keypad selection, without changing the levels of any channels which were under control.

4.2.1 Channel Selection
Channel numbers are selected on the keypad as on a calculator and appear in the CHAN/MEM (Channel/Memory) display window. If an attempt is made to change the level of a channel which does not exist, the Error alarm will sound momentarily and the display will blank.
An alternative method of selecting channels is provided by the NEXT and LAST keys. The NEXT key selects the next channel number and the LAST key the previous. When adjusting a sequence of channels, use of these keys makes the selection of the individual channel number digits unnecessary.

4.2.2 Setting Channel Levels
Following selection of a channel number, its level may be set by any of the following methods:
i) By operation of the '@' key, followed by a single digit, or by two digits separated by a decimal point ('.'). These digits represent levels on a scale of ten and may be considered as a percentage; thus 5 will set the selected channel to 50% and 5.5 to 55%. The FULL key selects maximum level (100%). The resulting channel level is shown as a percentage (maximum level is shown as '100') in the LEVEL display window above the fader wheel.
When the '@' key is pressed, the adjacent indicator lights to warn that the next entry will be interpreted as a level. Once the first level digit has been entered, the indicator is extinguished, but it will light again if the '.' key is
operated, to indicate that the least significant digit of the level may be entered.
Note that in the case of the FULL key, it is in fact unnecessary to first press the '@' key.
ii) By use of the fader wheel. Movement of this away from the operator increases the level of the channel and vice versa. One sweep of the exposed section of the wheel corresponds to slightly more than a fade from zero to full.
When a channel level has been set (by either of the above methods) the keypad becomes immediately available for a new selection. There is no need to operate the Clear (CL) key before selecting the next channel.

4.2.2.1 On at Zero
When a lighting state is memorised, channels which have been set to level 0 will be recorded as Off and these channels will then not take part in Move-fades involving the memory concerned. There are occasions, however, when it is required to fade some channels to zero and switch them Off while leaving others unaffected. This may be achieved by setting the channels which must fade out 'On at zero' in the memory.
When setting-up lighting, the selected channel(s) may be set into the 'On at zero' state by typing '@', '.' (decimal point); the channel(s) concerned will be shown at level '00' on the Video mimic. Note that when setting channels in this way, the CL (Clear) button on the keypad must be pressed before entering the next channel number, as the latter would otherwise be interpreted as a level.

4.2.2.2 Use of the ON Button
The ON facility provides a convenient method of rapidly setting channels which are Off to a preferred level. A separate 'ON' level (initially 70%) is stored for each channel and this level will be retained when the system is switched off.
What happens when the 'ON' button is operated depends on the On/Off state of the channel whose number is shown in the CHANNEL CONTROL display window (where a number of channels are selected as a group this will be the channel whose number was the last entered); there must be a valid channel selection, or the error alarm will sound. If the channel whose number is shown in the display is Off, the indicator associated with the 'ON' button will be off and pressing the 'ON' button turns the selected channel or channels On. If, however, the last selected channel is On, the 'ON' indicator lights and operating the 'ON' button turns the channels Off; in the latter case, the 'ON' level stored for each of the selected channels will be changed to that which was current immediately prior to operation of the 'ON' button.
The ON button will operate on individual channels or groups; groups may be selected using the '+', '-' and THRU buttons, or recalled from memory using the GRP (Group) button. The 'ON' button is inhibited, however, if a Move-fade is being controlled (see section 4.6.4).
Unlike on other Strand systems such as Galaxy, on Gemini the 'ON' level is also automatically updated when a lighting state is memorised; in this case, channels which are at levels above zero will have their the stored 'ON' level set to the last recorded level.
Stored Channel ON levels will be transferred to or from disc as part of Memory 0 and will be reset to 70% if the memory is re- initialised.

4.2.3 Modifying Channel Levels
The level of any channel which is already contributing to the lighting may be easily adjusted by selecting the channel required and then using the '@' key or the fader wheel.
If required, the '@' key may be used in conjunction with the '+' and '-' keys to adjust the level by a predetermined amount. For example, to raise channel 8 by 10% press 8, '@', '+', 1. Use of the decimal point as previously described allows modification to 1% accuracy. The LEVEL display always shows the actual level of the channel whose number is in the CHAN/MEM window. The effect of the '' master fader and any contribution from the Sub-masters are ignored.
The Channel Control is able to take control of any channel at any time and modify its level even if the channel is fading under the control of a Playback. When this becomes necessary, however, corrective action is usually required as quickly as possible because circuits are becoming too bright or are not bright enough; often in the time taken to type-in the channel number it is too late to stop the fade being spoilt. The Channel Control has special facilities therefore to help overcome this problem.
A channel which may need to be over-ridden during a Playback fade is selected up on the Channel Control. The fade is then started and by the latest-takes-precedence philosophy (outlined in section 4.1), control of this channel is passed to the appropriate Playback. If no further action is taken the channel remains under the control of the Playback until the fade ends. However, if the Channel Control fader wheel is moved, control of the channel is immediately and automatically transferred to the Channel Control, thus allowing that channel to be controlled manually.

4.2.4 Selection and Control of Groups of Channels
The ability to control the level of several channels simultaneously (i.e. as a group) is highly desirable and speeds up rehearsals considerably. The channels constituting a group may be selected individually by the following procedure:

1) Enter first channel, e.g. 2.
2) Enter '+'.
3) Enter second channel, e.g. 18.
4) Enter '+'. .
5) Enter third channel, e.g. 11.
Etc. ...
Channels 2, 11 and 18 would then be controlled together as one channel.
Similarly, a channel may be removed from control as follows:

1) Enter '-'.
2) Enter channel, e.g. 11.
The CHAN/MEM window shows the number of the last channel selected,
preceded by '+' or '-' as appropriate.
If all the channels selected are at the same level when taken under control they remain together when the fader wheel is moved. If, however, the channels are at different levels, an equal amount is added to or subtracted from each channel as they fade up or down. This type of fade is not proportional and is usually referred to as a 'Group' or 'Shaft' fade.
The wheel may be moved up until one-by-one all channels reach full. Moving the wheel in the reverse direction will then restore the original balance, while further downward movement reduces the levels until one-by-one the channels reach zero.
The THRU button may be used to call-up a contiguous group of channel numbers for control, as follows:

1) Enter the first number, e.g. 7.
2) Press THRU.
3) Enter the last number, e.g. 13.
THRU may also be used to remove a sequence of channels from control
by prefixing the first number with minus (-).
When using THRU, any numbers may be entered, but the second must be higher than the first or the Error alarm will sound. Similarly, the first number must be within the range of valid channel numbers. Only channels which exist within the range entered will be selected.
Note that the THRU button is inoperative if the keypad is being used for memory number selection.

4.2.4.1 Recalling Memorised Groups
An alternative method of selecting a group of channels for control is to call up a previously recorded memory. Considerable time may be saved at a lighting rehearsal if some basic 'building-blocks' of lighting have been set-up and recorded as memories. Such typical 'blocks' may be all the red channels of the cyclorama, or the channels in a blue wash for a night scene. These memories are recorded in the normal manner by selecting the required channels and setting levels, and then selecting a memory number and recording. The memory numbers used for these groups should be outside the range of numbers likely to be used for a production, and it is suggested that a set of numbers (for example, those above 900) be reserved for groups. This is extremely relevant if the groups that are set up are not specific to one production and may be used each time a show is lit, as it is obviously undesirable for these memories to be erased accidentally.
All the channels On in a recorded memory are taken under the control of the Channel Control by pressing the GRP (Group) button and then entering the number of the required memory on the channel keypad. Note, however, that no level is shown in the LEVEL display window if the last channel selection action was the recall of a recorded group.
Channels may be added to recorded groups or deleted from them in the usual way, by use of the '+' and '-' keys. Similarly, groups may be added together or their channels removed from control using the following procedure:

1) Press the GRP button.
2) Select the first memory number on the channel keypad.
3) Press the '+' or '-' button as required.
4) Press the GRP button a second time.
5) Select the second memory on the channel keypad.
6) If required, continue until the desired combination is obtained.

4.2.5 The RETURN Button
A feature of the fader wheel, owing to its 'positionless' character, is the ease with which channel levels may be modified. If, however, the initial level is not noted, it can be difficult to correct levels changed in error. To overcome this, an internal return memory is provided, which retains the starting level of each channel whenever a channel or group of channels is modified.
When a channel or a group of channels is selected and the level changed, the indicator adjacent to the RETURN button illuminates.
If the levels are then manually restored to within about 3% of their original settings the indicator is extinguished.
If a channel level is changed by mistake and a rapid return to the original level is necessary, pressing the RETURN button causes all the channels under control to be instantly returned to the levels which were current when they were selected. When this is done the RETURN indicator will be extinguished.

4.2.6 Flash
The Flash switch (labelled '') is a three-position centre-biased lever switch. When held in the up position, the channels selected on the keypad are turned on at full, while the down position switches them to zero. When the switch is released, the original channel levels are restored. Note that the Flash switch always operates directly on the system output, regardless of the Channel Control mode (i.e. O/P or SUB).
The most obvious use of the Flash switch is for lightning effects, etc. However, it may also be used to identify the contributions of individual channels to a complete scene. This is done by holding the switch up or down and stepping through the channels with the NEXT or the LAST key.

4.3 CHANNEL-TO-DIMMER PATCH
The Gemini Patch facility permits the connection of any channel on the system to any of the available dimmers; up to 384 dimmers may be used. Any number of dimmers can be allocated to each channel, but only one channel may be patched to each dimmer. In addition, lighting channels may renumbered, thus permitting a range of numbers to be allocated to each geographic area of the stage or studio; any channel number between 1 and 999 may be used.

4.3.1 Entering Patch Mode
When the PTCH (Patch) button on the Channel Control is operated, the
Video Mimic display changes to the following:

PAGE 1 OF 2 PATCH LAST REC 238.5 MEM USED 33%
001:001 @ +00% 002:002 @ 80% 003:003 @ +00% ...
006:006 @ +00% 007:007 @ +00% ...
011:011 @ +00% 012:012 @ +00% ...
016:016 @ +00% ... etc

The above shows the unchanged, 1:1 display. It consists of a list of dimmers, each of which is followed by the number of the channel to which it is patched and the 'patch level'. The latter is the level which will appear at the dimmer output, expressed as a percentage of channel level.
Entries for dimmers which have the normal 1:1 patch and an unchanged patch level are shown in dim yellow; entries which have been changed in any way are highlighted by appearing in bright yellow. When patch data is being entered, the selected dimmer is marked with a red background; at the same time any other dimmers which are patched to the same channel appear in red on a black background.

4.3.2 Changing the Patch
The Dimmer/Channel patch may be changed in several ways:

1) To patch a dimmer to a channel without changing the patch level, enter the Dimmer number and press the ON button; then enter the Channel number and press ON again. For example, to patch dimmer 149 to channel 76, enter '149, ON'; the display entry for dimmer 149 will be highlighted in red. Then enter '76, ON'. The appropriate item in the dimmer list will change to '149:076 @ +00%' and will return to its normal yellow
colour; it will now, however, appear brighter on the display than the unchanged entries.
2) To change the patch level of a dimmer without changing the dimmer-to-channel assignment enter the dimmer number and press the '@' button; then enter the required level and press the ON button. For example, to change the patch level of dimmer 149 to 80% enter '149, @, 8, ON'; the appropriate item in the dimmer list will change to '149:149 @ 80%'. Note that the dimmer-to-channel assignment remains unchanged.
Any patch level between 0% and 99% may be entered, either as a single digit, or as two digits separated by a decimal point. These represent levels on a scale ten and will be displayed as a percentage of full level; thus 5 will select a patch level of 50% and 5.5 will select 55%. If the first digit is preceded by '+', the percentage entered will be added to full level, thus allowing the dimmer level to be higher than that of the channel; note, however, that dimmers patched in this way cannot be driven higher than full and will therefore exhibit a 'plateau' effect at higher channel levels.
The normal 1:1 patch level is entered as '+0' and appears on the display as '+00%'.

3). To change both the dimmer-to-channel assignment and the dimmer patch level, enter the dimmer number, press ON and then enter the channel number; then press '@' followed by the required patch level. For example, to patch dimmer 149 to channel 76 at a patch level of 80%, enter '149, ON, 76, @, 8'; the appropriate item in the dimmer list will change to '149:076 @ 80%'.

4) Unused dimmers may be removed from the patch by entering the dimmer number, pressing ON and then clearing the keypad with the CL key before pressing ON the second time. Dimmers removed in this way will disappear from the 'PATCH' display, leaving a blank space.

4.3.3 Geographic Patching
When patching dimmers to channels, any channel number from 1 to 999 may be used, thus allowing groups of channel numbers to be allocated to different geographic areas of the stage or studio. It is not possible, however, to use more channel numbers than there are channels in the system (normally 180), and a channel must be 'released' before a new number can be brought into use. The operations required are as follows:

1) Decide which of the existing channels is to be renumbered and enter the number of the dimmer to which this is currently patched.
2) Press ON, CL, ON to remove this dimmer from the display.
3) Repeat for any other dimmers to which the channel is patched.
4) Enter the number of the dimmer to which the new channel is to be patched. Then press ON.
5) Now enter the new channel number and press ON a second time.
6) Repeat the last three steps for any other dimmers which are to be patched to the new channel.
The error alarm will sound if any illegal actions are attempted.

4.3.4 Using the Patch Facility

4.3.4.1 Memory Back-up System
When the Gemini Memory Back-up system is in use, the Channel-to-
dimmer patch is NOT taken into account. If possible, Back-up memories should be prepared which minimise the need to control individual dimmers.

4.3.4.2 Manual Fader Wing
When a Manual Fader Wing is provided, there are some restrictions on the use of the Patch facility. Firstly, because it is not possible to renumber the manual wing faders full geographic patching is not possible; the maximum available channel number is limited to the number of channels in the system (normally 180). Secondly, any Channel-to-dimmer patch will not be effective if the Gemini desk is not in operation; it is recommended that patching be kept to a minimum, so that control may be easily transferred to the Manual Fader Wing should a breakdown of the main system occur.

4.4 OUTPUT CONTROL
4.4.1 The Blackout Switch
In the down () position, this switch turns Off all control signals to the dimmers from the Gemini system; the message 'BLACKOUT' appears on the Video Mimic. When returned to the up () position, the switch restores the previous lighting. The blackout switch does not stop fades progressing nor alter any system modes.

4.4.2 The Output Master Fader
If this fader is moved down from 'F' towards '0', the lighting scene set on the Gemini system (including the Sub-masters) is proportionally faded out; returning the fader to 'F' restores the lighting. Any fades which are in progress continue to run while the fader is below maximum and all system modes are unaltered.

4.5 SELECTION OF MEMORY NUMBERS

4.5.1 General
The MEMORY CONTROL keypad is used for selection of memory numbers for recording, or for recall to the Playbacks or the system output. Any integer between 1 and 999 may be selected on the keypad and a lighting state recorded in the associated memory. In addition, nine memory numbers, identified by a digit following a decimal point, are available between each integer, e.g. 32.1, 32.2, 32.3, etc.

Normally, when recording, integer numbers would be used first (1, 2, 3, etc.) and then, if it became necessary to insert a state between memory 2 and 3, for example, memory 2.5 could be used.
Memories may also be selected using the NEXT and LAST keys. NEXT steps the number to the next highest memory number recorded; LAST steps it back to the next lowest recorded memory, rolling through zero.
If an attempt is made to recall a memory which has not been recorded, the Error alarm will sound. The number is then regarded as having been used and subsequent entry will be treated as a new number.
The number selected will be used when any of the following buttons are operated: '?' (Preview); any of the Record buttons; any of the memory recall buttons (i.e. the Output 'MEM' button, either of the Playback FADE buttons and any of the Sub-master 'MEM' buttons); PRNT (Print); and either of the disc action buttons, MEM-DISC or
DISC-MEM. Once a memory number has been used for recording or playback, any subsequent entry on the keypad is assumed to be a new number, making it unnecessary to press CL (Clear) before every entry. The CL key need only be used if an incorrect number has been typed in or when clearing the keypad prior to initiating a fade to blackout.

4.5.2 Combining Memories with the Plus (+) and Minus (-) Keys
As in the case of channels, which may be combined into groups, memories may be combined prior to recall by means of the Plus and Minus keys. In addition, these keys may be used to prefix a memory number in order to affect the way in which the memory combines with the current output when a memory recall button is operated.
When recording, if the memory number is prefixed with a Plus or Minus sign, the prefix will also be memorised so that the required fade type will be selected automatically when the memory is recalled in Sequence mode (see section 4.6.2.6).

4.5.2.1 Adding Memories
Any memory may be added to the existing channels contributing to the output by prefixing the memory number with '+' on selection. While a normal fade would totally substitute the selected memory for the previous lighting (Crossfade), the recall of a memory with a plus prefix will simply add in the extra channels at their memorised levels (Move-fade). A channel which is On both at the output and in the memory added, will be set, on completion of the fade, to the memorised level, in accordance with the 'Latest-takes-precedence' philosophy.

4.5.2.2 Subtracting Memories
If a memory number is prefixed with minus, the channels which are On in the memory will fade to zero at the output when recalled.

4.5.2.3 Combining Memories Prior to Recall
Memories may be combined prior to recall using the Plus and Minus buttons in the same way as when combining channels into groups. In the case of common channels, the resulting level will be in accordance with the Latest-takes-precedence philosophy. If a memory number is prefixed with Minus, the channels On in the memory will be removed from the combination.
As in the case of individual memories, whole groups may be prefixed' with '+' or '-'. The complete combination will then combine with the current lighting as described in sections 4.4.2.1 and 4.4.2.2 above.

4.5.3 Memory Preview
The button labelled '?' changes the mimic display while held down; the lighting state recorded in the selected memory is shown.

4.5.4 Memory Full Warning
As described elsewhere, the number of memories available to a Gemini system is dependent on the capacity of the memory fitted and the number of channels On in each state recorded. A tally of memory used is, therefore, constantly shown on the top line of the Video mimic. If an attempt is made to record a memory which requires more space than is available the action is aborted and the following error indications given:
i) The Error alarm sounds momentarily.
ii) A 'MEMORY FULL' message appears on the Video mimic.
iii) The appropriate RECORD button does not light.

The only immediate action possible is to clear some memories, if necessary first storing them on a disc.
The error messages may be cleared by re-selecting the current Video mimic display.

4.5.5 Clearing Memories
It is not strictly necessary to clear a memory before that number can be used to record again, as a recorded memory will be overwritten if the record button is pressed twice in close succession. However, when lighting a production it is sometimes desirable to start with a 'clean slate' so that old and new lighting does not become confused, and the progress of recording can be clearly seen with Memory List.
Any or all memories may be erased by using the CLEAR position on the Record Lock keyswitch. When erasing more than one memory, the THRU button on the MEMORY CONTROL keypad may be used to select a range of numbers.
The memory clear operation is interlocked to prevent accidental erasure. The following procedure is required:

1) Select the first memory to be cleared.
2) If erasing a range of memories, press the THRU button; the associated indicator illuminates. Then enter the the number of the last memory in the range.
3) Insert the key (TOK 4) into the Record Lock keyswitch and turn it 90º clockwise to enable recording.
4) Rotate the key a further 45º against the spring to the CLEAR position and while holding it there press 'REC~'. This requires the use of both hands.
The 'REC' button will light momentarily, the indicator above the THRU button will be extinguished and the 'MEMORY USED' display will be updated as the extra memory becomes free.

4.5.5.1 Memory Initialisation
The one situation where it is essential to clear the memory is if the memory directory is corrupted; this should only occur if a memory board has been exchanged, or if the batteries have become discharged.
Memory initialisation is carried out by clearing memories 0 THRU 999.9 as described above; the memory will be totally erased, and a new directory written. Note that this procedure will also erase the Channel-to-dimmer patch and the recorded effects; these must then be re-entered, either manually or from Floppy Disc.

4.6 RECORDING

4.6.1 General
Once a Lighting scene has been set-up to the operator's satisfaction, it may be recorded in the memory. The data is not stored in the system's long term memory until a record button is pressed. To prevent unauthorised or accidental modification of memories, a Record Lock keyswitch is fitted; the key may only be removed from this if the memory is Locked.
Record actions are disabled under the following circumstances:
i) If the Memory Lock keyswitch is not in the OPEN position.
ii) If no memory number is selected.
iii) If the memory is full.
iv) If the selected memory number is that of an existing memory.
In this case, however, a second operation of the Record button (within 2 seconds) will overwrite the old memory.
Separate record buttons are provided for recording channel Levels from the output or from the Sub-masters, for recording Fade and Wait times and for recording Links to memories. Most of these buttons are red in colour to emphasise their function; exceptions are LINK and WAIT.
If the memory number is prefixed with a Plus or Minus sign when recording, the prefix will also be memorised. The required fade type will then be selected automatically when the memory is recalled in Sequence mode (see section 4.6.2.6).
Note that if an existing memory includes a Link, this will be unchanged when a new or modified Lighting state is recorded in that memory. This is obviously desirable when modifying existing memories, but if a new memories has been created it will be
necessary to delete the Link after recording (see section 4.5.6).

4.6.2 Recording System Output (REC)
When pressed, this button copies the total Lighting state currently seen into the selected memory. The state recorded is that displayed on the Video mimic when a!p is selected and includes the effect of the Grand Master fader. Lighting contributed by the Sub-masters is included, as is that contributed by an external Manual Fader Wing, if this is connected via Rank Strand Multiplex Interface Units (see section 1.1).
Recording may take place at any time, even while fades are in progress, the lighting set-up remaining totally unaffected.

4.6.3 Recording Blind
It is often necessary to set-up lighting while the stage is in use and it is useful under these circumstances to be able to record new scenes without affecting the current output state. To facilitate this, a REC SUB (Record Sub-masters) button is provided, which records the lighting contributed by the selected Sub-master; the settings of the various master faders are ignored, thus allowing lighting to be prepared and recorded 'blind', with the appropriate Sub-master at zero.

4.6.4 Making a Copy of a Memory
If a copy of an existing memory is required, this may be made by recalling the memory concerned, selecting a new memory number and re-recording.

4.6.5 Recording Time
The time taken for a fade when a memory is played-back may be recorded with each memory. However, as details of fades are not always known at the rehearsal where lighting is being set, recording time is a separate operation which may therefore be performed at a later time.
Each Playback has a REC TIME push which, when pressed, stores the time currently set on the associated Fade Duration controls with the memory selected on the Memory keypad; if either Fade Duration control is at '00', the appropriate time will be recorded as 20 minutes. The recorded channel levels will not be affected; similarly re-recording the channel levels will not change a previously recorded time.
It is possible to record a time 'manual', so that Manual mode will be selected automatically when the memory is recalled to a Playback (see section 4.6.2.4). The latter is achieved by pressing the 'MAN' button on the appropriate Playback to select manual mode before pressing the REC TIME button. Manual mode may then be cancelled by pressing MAN a second time.

4.6.6 Recording Links
When recalling memories on a Playback with Sequence (SEQ) selected, the next memory in numeric sequence will normally be automatically selected each time a fade is started, ready for recall. It is, however, possible to change the order in which the memories are recalled by recording a link, i.e. the number of the next memory
required in the sequence, with each memory. If no link is recorded with a memory, the normal numeric sequence will be used.
The link facility allows the insertion of additional memories in a numeric sequence and allows memories to be recorded as convenient and put into the required order for playback when this has been finalised.

Links are recorded as follows:
1) Ensure that recording is enabled.
2) Enter the number of the memory with which the link is to be
recorded.
3) Press the LINK button. The associated indicator will light and any existing link will be shown in the keypad display window.
4) If required, enter the new link memory number.
5) Press LINK a second time. The associated indicator will be extinguished and the number of the selected memory will again appear in the display window.

For example, to cause memory 84 to be inserted between memories 16 and 17, when recalled with SEQ selected, a link to number 84 must be recorded with memory 16 and memory 84 should be linked to number 17 as follows:
1) Enable recording.
2) Select memory 16 on the MEMORY CONTROL keypad. 3) Enter LINK, 84, LINK. 4) Select memory 84.
5) Enter LINK, 17, LINK.
A link may be cleared by entering the required memory number followed by LINK, Clear (CL), LINK.
If recording is not enabled links may still be examined using the LINK button. Under these circumstances, however, links may not be changed and the window will return to its previous display when the button is released.

4.6.7 Recording WAIT Times
If a Playback has USE TIME selected, it will operate using Wait times which may be recorded with each memory. A Wait time determines the time between the start of one fade and auto-execution of the next; if the next memory in sequence (taking into account any recorded link) has a Wait time, a fade to the memory concerned will begin automatically when the Wait time has expired. A countdown of the Wait time will appear at the bottom of the appropriate Playback Status display on the Video Mimic. Complex fade sequences may thus be performed completely automatically.

Wait times are recorded as follows:
1) Enter the required memory number on the MEMORY CONTROL keypad.
2) Press the WAIT button beside the keypad; the associated indicator illuminates to show that Wait mode is selected. Any previously recorded Wait time is shown in the MEMORY CONTROL display.
3) Enter the required Wait time.
4) Press WAIT a second time to perform the record action; the WAIT
indicator extinguishes to show that the Wait time has been recorded.

Any time between 0 and 19 minutes 59 seconds may be entered, as follows:

i) A time of zero (instant) is entered by pressing the decimal point only.
ii) Times of less than 10 seconds are entered as seconds and tenths of seconds, separated by a decimal point; e.g. for a time of 5.7 seconds enter '5', '.' (point), '7'.
iii) Times longer than 10 seconds and less than 100 seconds are entered as two digits with no decimal point; e.g. for a time of 45 seconds enter '4', '5'. When the WAIT button is pressed the second time, this will be automatically converted to minutes and seconds if appropriate. If, following entry of the digits, the decimal point key is pressed the Error alarm will sound.
iv) Times longer than 1 minute are entered as three or four digits, with no decimal point; e.g. for time of 5 minutes 30 seconds enter '5', '3', '0'. If the number of seconds is greater than 59, these will be converted to minutes and seconds as before. As in the previous case, the Error alarm will sound if the decimal point key is pressed following entry of the digits.
If a time greater than 19 minutes 99 seconds is entered the display will blank and only the last digit entered will appear. Times between 19 minutes S9 seconds and 19 minutes 99 seconds will be automatically reduced to 19 minutes S9 seconds.
A Wait time may be cancelled by pressing WAIT, followed by CLEAR or '0', and then WAIT a second time.
Recording a Wait time with a memory does not affect previously recorded channel levels, fade times or links.
If recording is not enabled, Wait times may still be examined using the WAIT button. Under these circumstances, however, Wait times may not be changed and the window will return to its previous display when the button is released.

4.7 MEMORY PLAYBACK

4.7.1 General
There are three ways in which memories can be recalled on Gemini. The normal method is by using one of the two Playbacks. The memories are selected on the keypad in Memory mode, the fade time set on the appropriate Up () and Down () Fade Duration controls and the fade is started by pressing the corresponding FADE button. The fade is then carried-out automatically and completes in the time set.
A second method is by use of the 'MEM' (Memory Recall) button above
the '' Master Fader. This allows the memory displayed in the memory number window to be 'cut' immediately to the system output; memories may thus be recalled very quickly, without the need to use a playback. Alternatively, the selected memory may be recalled to one of the eight Sub-masters (see section 4.7.2); the lighting may then be introduced as a manual fade or that assigned to a number of Sub-masters may be rapidly balanced using the corresponding faders.
The third method of recalling memories is intended for use when setting-up lighting and involves using the Channel Control in Move mode. This mode is selected by means of the MOVE button above the keypad and permits the selection of memories on the Channel Control; these are then introduced by moving the fader wheel upwards or by setting a level using the '@' button.

4.7.2 Fade System
When using either automatic fade system, the fade times must first be set on the appropriate Fade Duration controls, or alternatively, the fade times recorded with each memory may be used by selecting USE TIME (the adjacent indicator lights when this facility is selected). The fastest fade rate is almost instant, for 'snap' cues, while at the slowest speed a fade will take 20 minutes to complete. The Lowest position on each control is an infinity (00) setting, at which the fade is stopped. Separate times may be set for those channels increasing and those decreasing in intensity, using the '' (up) and '' (Down) Fade Duration controls respectively.
When the FADE button is pressed to start a fade, the associated indicator Lights and the number of the incoming memory is shown in the ACTIVE MEMORY display window. The progress of the fade is shown on the Up and Down column indicators on either side of the Fade Duration controls. The FADE indicator remains Lit until the fade completes, while the memory number remains displayed after completion until another fade is started.
A total of up to twenty four fades, started on either or both Playbacks, may be running at once and the Last of these to be started by each Playback may be speeded-up, slowed-down, completed instantly or halted by adjusting the settings of the appropriate Fade Duration controls (USE TIME must first be de-selected - see section 4.6.2.7). It is also possible to manually profile a fade, using the Fade Duration controls as master faders - see section 4.6.2.4.

4.7.2.1 Crossfades and Move-fades
When a memory is selected for recall, it will normally have no prefix and, when faded, will completely replace the current output. However, if the memory number is given a prefix ('+' or '-') the memory will be added to (or subtracted from) the current Lighting. These two types of fade are known as Cross fades and Move-fades respectively.
When the memory number is given a '+' prefix, the Move-fade changes those channels which are On in the memory from their current Levels to their memorised Levels. If the prefix is '-', however, the channels which are On in the memory will fade to zero at the output; this is a special type of Move-fade, sometimes called a 'Dim-fade'. Move-fades are usually used to add channels or to remove them from an existing scene. Gemini may perform several Move-fades, at different speeds, simultaneously.
A Cross fade (i.e. a fade to a memory selected without any prefix) substitutes the scene in the memory for the current Lighting, including channels which are not On in the memory - the Latter fade to zero. To do this, all channels are taken under control and thus only one Crossfade may take place at a time, the Latest cancelling
any previous Cross fades and Move-fades.

Fades do not affect lighting contributed by the Sub-masters. All fades are 'dipless'; channels progress linearly from old to new levels and channels which are at the same level in both states do not change during the fade.

4.7.2.2 Instant Fades
Any fade may be actioned instantly by pressing the INST (Instant) button at the same time as pressing FADE. If INST is pressed while fades are running the latest fade on the corresponding Playback will complete instantly.

4.7.2.3 Reversing a Fade
When the REV (Reverse) button is pressed it lights, and reverses the direction of the last fade started, restoring the original lighting. The reverse fade is carried out at the same speed as the forward fade, but, provided USE TIME is not selected, this may be adjusted at any time by using the Fade Duration controls.
Pressing the REV button a second time causes the fade direction to change again, thus repeating the original fade. Note that the FADE button should normally only be used to start the next fade; it will not necessarily produce a repeat of the same fade.

4.7.2.4 Manual Fades
The need to manually profile a fade to match the action is quite common, particularly in theatre or television drama. Manual fades may be carried out on Gemini as follows:
1) Select the next memory on the MEMORY CONTROL keypad, prefixing the number with '+' or '-', if required, to determine the type of fade.
2) Press the MANUAL button. The associated indicator lights to indicate that Manual mode is selected (if USE TIME is in use, this must first be deselected).
3) Press the FADE button to start the fade. The associated indicator lights to indicate that the fade is under control.
4) Move the Fade Duration controls, which are now manual masters, to the bottom to 'collect' the fade. The fade is then actioned by moving the controls from the bottom to the top at the required rate; the Fade Progress indicators on either side of the faders will track the movement of the two faders.
The fade may be reversed at any time by simply moving the faders down again.
Manual mode may be selected or de-selected while a fade is in progress. In the former case, the fade will stop and the faders must then be moved to the top or bottom before being matched to the appropriate point of progress using the Fade Progress indicators beside the faders. The faders will not collect the fade unless they have first been moved to one end; choose the end which will allow the faders to continue in the required direction when the fade has been collected.
If Manual mode is de-selected while a fade is in progress, the fade will immediately resume at the speed currently set on the faders. If USE TIME is selected, this will have to be de-selected before the speed can be adjusted.
If it is known that a particular fade will be carried-out manually at each performance, a 'time' of Manual may be recorded (see section 4.5.5). Manual mode will then be selected automatically if the memory is recalled with USE TIME selected.
Note: Because only the latest fade may be controlled by the Fade Duration controls, it is impossible to continue a Manual fade on the same Playback once another fade has been started. As a result, only one manual fade may be in progress on each Playback at a time.

4.7.2.5 Multiple Move-fades
As indicated in section 4.6.2, up to twenty four fades may be in progress at once, each at different speeds. These may be on either Playback, but each Playback may also control multiple Move-fades. On each Playback, as each fade is started, control of the previous one is lost and it continues at its last speed setting until it completes or until a Crossfade is started. This means that Manual fades will, in effect, cease to run once the next fade is started. When a Crossfade is started all other fades will stop, leaving only the Crossfade.
If there are twenty four fades already in progress and a twenty fifth is started, the fade which is closest to completion stops.

4.7.2.6 Sequential Playback of Memories
When a fade action has been started, the next memory required may be selected on the keypad. Alternatively, the system may be switched to Sequence mode.
When the SEQ button is pressed, the associated indicator lights. Then, each time a fade is started, the next memory is automatically selected ready for the next fade. The next memory in numeric sequence will normally be selected, but any recorded links will be taken into account.
When Sequence is in use, holding down the '?' (Preview) button and then pressing SEQ will cause the contents of the next memory in the appropriate sequence to be displayed on the Video Mimic.

4.7.2.7 Using Recorded Times
The current settings of either pair of Fade Duration controls are recorded in the selected memory when the corresponding REC TIME button is operated (see section 4.5.5). The recorded times will only be used, however, if the USE TIME button has been pressed (the associated indicator lights to indicate that USE TIME is selected).
When a memory is recalled with USE TIME selected, the current settings of the Fade Duration controls will be ignored and adjusting them will have no effect. However, the latest fade may be speeded- up or slowed-down if USE TIME is deselected. It is best, though not essential, to match the Fade Duration controls to the current fade times before deselecting USE TIME mode, so as to avoid a sudden change of speed. The Fade Time displays on the Video Mimic permit this to be done.
USE TIME mode may be reselected immediately if required, ready for the next fade action. The current fade will continue at the speed which was set on the Fade Duration controls at the moment USE TIME was reselected.

4.7.2.8 Recorded Wait Times
If required, the Playbacks may operate using Wait times recorded with each memory. These are used to determine the time between starting one fade and auto-execution of the next. When this facility is used, fade actions will take place completely automatically, using, in addition to Wait times, the Fade times and Fade Types which may be recorded with each memory.
If a memory has a recorded Wait time, and USE TIME and SEQ are selected, executing the previous fade will start a Wait countdown, auto-execution of the second fade occurring at the end of the Wait time. If there is no Wait time, the fade must be initiated using the fade initiation buttons in the normal way.
Wait times may be over-ridden in two ways: a Wait may be cut short by pressing the appropriate FADE button; or it may be lengthened by de-selecting USE TIME and then initiating the fade with the FADE button. Once USE TIME has been de-selected, it may be reseLected without restarting the Wait countdown.

4.7.3 Memory Recall directly to the Output Store (MEM)
The memory recall button immediately above the' 2:' Master fader allows the memory displayed in the memory number window to be 'cut' immediately to the system output. The purpose of the button is to allow memories to be replayed very quickly, without the need to use a Playback. The effect which is produced is that of an instant crossfade, clearing any previous Lighting and substituting the new state. Any contribution to the scene from the Sub-masters remains unaffected. Any fades which may be in progress when the button is operated are immediately halted.
Note that if the memory number is prefixed with a Plus or Minus the existing Lighting will not be cancelled and the memories will combine as outlined in section 4.4.2.

4.7.3.1 Random Cut
If the Output 'MEM' button is held depressed, memories may be cut to the output, simply by selecting them on the memory keypad. In practice, only memories with whole numbers between 1 and 9 may be recalled in this way, although, if required, the NEXT and LAST buttons may be used.

4.7.3.2 Instant Blackout
During rehearsal it is often desirable to cancel all the current f Lighting and start again from a blackout. This is best achieved by recalling memory a or 'Blank' to the system output by use of the Memory Recall button ('MEM'). The associated indicator will be ' extinguished, all channels switched Off and all fades cancelled. The Sub-masters remain unaffected and, if a totally clear state is required, they must be wiped individually by recalling memory a to each in turn. If the Sub-masters are not in use, the Sub-master Grand Master fader may be set to zero to avoid confusion.

4.7.4 Recalling Memories using Channel Control Move Mode
An alternative method of recalling memories is provided; this is the Move mode on the Channel Control. This is primarily intended for use during lighting rehearsals. It allows previously recorded memories to be used as building blocks in the design of new lighting scenes; each memory can be added proportionally until the required effect is produced. For example, if separate memories are prepared containing the red, blue and green cyclorama channels at pre-balanced levels, these may then be introduced by means of Move mode and balanced using the fader wheel.
Move mode also permits the operator to use the Channel Control as a third Playback, thus giving simultaneous manual control of three dipless fades.
Note: It is recommended that, if it is intended to use the Channel Control in Move mode while recalling memories on the Playbacks, only Move-fades be recorded. If Crossfades are used, the Latest-takes-precedence philosophy will mean that each time a new fade starts, the channels under Move control will be 'stolen' by the fade system.
Move mode is selected by pressing the MOVE button above the Channel Control keypad; the associated indicator lights and the previous selection is cancelled. If a memory number is now entered, the corresponding memory may be introduced as a Move-fade by moving the fader wheel upwards. Both up and down parts of the fade occur simultaneously and, once the channels concerned have reached their recorded levels, further forward movement of the wheel has no effect. The fade may be reversed by moving the wheel towards the operator until the starting levels are restored or, for a rapid return to the original state, the RETURN button may be used. The progress of the fade is shown as a percentage in the LEVEL display window.
As an alternative to using the fader wheel, the '@' key may be used in conjunction with the keypad. The 'level' entered is interpreted as the percentage of the fade which is to be carried out and the channels are set immediately to the levels that they would reach by fading. For example, MOVE, 10, '@', 5 would switch channels from
their current levels to the levels they would reach half-way (50%) through a Move-fade to memory 10.
Only Move-fades may be carried out in this way, entering the memory number without a prefix having the same effect as using a '+' prefix. The '_I prefix, however, will still produce a Dim-fade, the channels on in the memory fading out as the wheel is moved upwards.
As on the Memory Control keypad, memori es may be combined in r'1ove mode before being introduced; see section 4.4.2.3. Note, however, that once a fade has been carried out, the keypad will automatically revert to channel selection mode on entry of the next number; each memory or group selection must therefore be preceded by operation of the MOVE button, as follows:
1) Press the MOVE button.
2) Select the first memory on the channel keypad.
3) Press the '+' button.
4) Press the MOVE button.
5) Select the second memory.
6) Continue until the required combination is obtained.
As on the Memory Control keypad, the THRU key may not be used to
select a contiguous sequence of memory numbers for recall; the system alarm will sound if this is attempted.

Note: If additional channels or groups are added to a combination prepared using Move mode as above, the whole selection becomes a group and the fade changes from a 'Move' to a 'Group' or 'Shaft' fade. This is because there are no recorded destinations for the additional channels.

4.8 THE SUB-MASTERS PANEL

4.8.1 General
This section of the control panel comprises eight Sub-master faders, each of whi ch has an associated Memory Recall button (MEM). At the top of the panel is a row of eight buttons (each with an associated indicator) labelled A, B, C, etc. which are used to select the required Sub-master when using the Channel Control in SUB (Sub- master) mode, or when recording lighting states using the REC SUB button. Above the latter buttons is a display window which shows the number of the memory (if any) last recalled to the selected Sub-master store.
The eight Sub-master stores are totally independent of each other. Each may hold a complete lighting scene, which may include channels set at different levels in other Sub-master stores or at the output. The outputs of the eight Sub-master stores combine on a highest-takes-precedence basis, and the combined output may be controlled: using the Master fader labelled A-H.

4.8.2 Setting-up lighting using the Sub-masters
Lighting may be set up either 'blind' or 'live- in anyone of the eight Sub-master stores, using the Channel Control set to SUB. The Sub-master store required is selected by means of the selection buttons (A, B, C, etc.) and the setting of the appropriate master fader determines the blind/live state (Note that the A-H Fader must be above zero when working live). Channels selected and adjusted on the Channel Control will immediately be set in the appropriate Sub- master store and the indicator adjacent to the Memory Recall (MEM) button will light to show that the Sub-master is in use. Adjusting the Sub-master fader will then vary proportionally the levels of all the channels set in the corresponding Sub-master store.
The Lighting controlled by any of the Sub-masters may be recorded independently of any other Lighting by means of the REC SUB button. The required memory is selected on the MEMORY CONTROL keypad, and the Sub-master store by means of selection buttons A to H. Note that the channel Levels recorded will be those in the Sub-master store. No account will be taken of any master fader settings.

4.8.3 Recalling Memories to the Sub-masters
A memory may be recalled to a Sub-master at any time by selecting the required memory on the MEMORY CONTROL keypad and pressing the appropriate Memory Recall (MEM) button. Unless the number is prefixed by '+' or '-', the previous lighting in the store will be completely replaced with the new. The corresponding Sub-master selection indicator need not be illuminated. If the memory number selected is prefixed by '+' or '-', the new memory will combine with that already present in the Sub-master store as described in Section 4.4.2.
The number of the Last memory recalled to the selected Sub-master store (prefixed by '+' or '-' if appropriate) is displayed in the window at the top of the Sub-masters section of the control panel.

4.8.3.1 Gang-Loading the Sub-masters
This facility allows a number of Sub-masters to be simuLtaneousLy Loaded, each with a different memory from a range selected on the memory keypad. Only memories which exist will be used.
The facility is best understood by means of an example. Memories 12, 13.5, 14 and 16 have been recorded and these are to be loaded onto Sub-masters D to G. First select memories 12 'THRU' 16 on the memory keypad and then press the Sub-master D 'MEM' button. The memories will be simultaneously loaded, 12 onto Sub-master D, 13.5 onto E, 14 onto F and 16 onto G. The first memory in the range is always Loaded onto the Sub-master whose 'MEM' button is operated and the memories are assigned in numeric order.
If required, the range of memories may be left open ended. For example, 1 THRU MEM(A) will assign each of the first eight memories to a Sub-master. The masters to the left of that on which the '+MEM' button is operated will remain unaffected.
Selecting CLEAR, THRU on the memory keypad allows the Sub-masters to be simultaneously cleared.
Note: Although, in general, memories may be combined before recall by using the '+' and '-' keys on the memory keypad, this is not possible when gang-loading the Submasters. If simultaneous entry of both a memory combination and a range of memories is attempted on the memory keypad, the error alarm will sound.

4.8.4 Sub-master Mimic Display
The contents of any of the Sub-master stores may be displayed on the VDU by holding down the appropriate Sub-master selection button.
The contents of the selected Sub-master store will also be shown when using the Channel Control in Sub-master mode. The channel levels shown will be those in the appropriate store, with no account taken of master fader level, etc.

4.8.5 Common Channels
If the same channel is On in one or more Sub-master stores, the level which appears at the system output will be that produced by the highest combination of channel and fader level, i.e. the level is subject to a 'Highest-takes-precedence' rule. For example, if channel 15 is at full in Sub-master A and at 50% in Sub-master B, and both faders are fully raised, the output level of that channel will be Full. If fader A is now lowered, the channel will dim until 50% is reached, when the level produced by Sub-master B becomes the higher. To reduce the level further, both faders must be lowered.
The combined outputs of the Sub-masters and the main system output are also subject to the 'Highest takes Precedence' rule.

4.8.6 The A-H Master Fader
The combined output of the eight Sub-masters may be reduced proportionally to zero by means of the A-H Master fader to the right of the Sub-master faders.

4.8.7 Using the Sub-master Faders in Inhibit Mode
If required, individual Sub-masters may be set into Inhibit mode. They can then be used to proportionally reduce the output levels of selected channels, the channels concerned being selected by setting them On in the appropriate Sub-master store. Any number of channels may be inhibited in this way by a single Sub-master fader.
A Sub-master is set into Inhibit mode by holding down the INH (Inhibit) button to the right of the faders and then operating the 'MEM' button above the required Sub-master fader; the appropriate Inhibit indicator (above the 'MEM' button) lights to show that the Sub-master is in Inhibit mode. Inhibit mode is cancelled by repeating the above actions.
The Sub-master inhibit facility does not simply reduce the maximum Levels of the channels concerned, but actually reduces the levels in proportion. For example, if a channel set to 50% is also On in a Sub-master store working in Inhibit mode, and the Sub-master fader is set to 50%, the resulting channel output will be 25%. If the Sub-master concerned is at Full, it will have no effect.
If the same channel is assigned to more than one Sub-master working in Inhibit mode, the Lowest of the Sub-masters will take precedence.

4.9 VIDEO MIMIC

4.9.1 General
The Video Mimic is normally used to display the combined outputs of the Gemini system and the Manual Fader Wing (if provided - see section 1.1) showing the channels which are On, together with their Levels. It may, however, be switched to display the Lighting set in any Sub-master store or recorded in a memory. In addition, it may display a List of memories, the Channel-to-dimmer patch or the set-up information for the Effects panel.

4.9.2 Screen Format
The screen is divided into two sections, the top part normally displaying the channels controlled by the system, while the bottom part shows system status information such as fades in progress, selected memory, etc.
The top Line of the screen is used to show headings and details of the system's memory:
Line 1 Example:

The bottom part of the screen is is divided into five sections: 'SUBMASTERS', 'MEMORY', 'GREEN PLAYBACK', 'RED PLAYBACK' and 'CHANNEL'. This status information remains unchanged as the various alternative displays are selected.

4.9.3 Sub-masters Status Display
Under the heading 'SUBMASTERS' is shown the number of the Last memory recalled to each of the eight Sub-masters. Sub-masters which are operating in Inhibit mode (see section 4.7.7) are highlighted in inverse video.

Example:

The bottom Line of the 'SUBMASTERS' display gives details of the current Effect.

4.9.4 Memory Control Status Display
Under the heading 'MEMORY' are displayed the currently selected memory, the fade times and Wait time (if any) recorded with that memory and the memory to which the selected memory is Linked, if any. For example:

The 'UP', 'DN', 'WT' and 'LK' displays do not appear if there is no memory selected, 'WT' appears only if the selected memory has a Wait time, and 'LK' appears only if the selected memory has a Link recorded.
Note: When a range of memories is selected (e.g. for recall to the Sub-masters or for copying to or from disc) the memories concerned are shown as follows:

4.9.5 Playbacks Status Display
Below each of the headings 'GREEN PLAYBACK' and 'RED PLAYBACK' in the bottom half of the screen are two sub-headings, 'UP' and 'DOWN', and below these, up to three Lines of information about fades which are in progress.
When the system is first switched on, or following the recall of memory a directly to the output (using the '+MEM' button above the 'E' master fader), only the settings of the corresponding Fade Duration controls are shown. When a fade is started on the associated Playback, the following information appears: type of fade ('M' equals Move-fade, 'D' equals Dim-fade and 'X' equals Crossfade); active memory at start of fade; up-fade time ('minutes'.'seconds'); up-fade progress; down-fade progress; and down-fade time. For example:

Each time a new fade is started, the appropriate status information appears on the top Line and the details of any other fades which are running move down to make room. If the new fade is a Crossfade, all other fades will stop (see section 4.6.2.1) and their details will be removed from the display. Similarly, as each fade completes, it is removed Leaving a blank Line. The Latest fade, however, remains on the screen.
If either Fade Duration control is at '00', the appropriate fade time is shown as '**.**'. If the fade is completely stopped (i.e. both controls are at '00') and another fade is started, the fade which was stopped disappears from the display, as it cannot now be restarted.
The bottom Line of the Playback status display only appears if Sequence is selected. It will then normally show the fade type, number and recorded fade times for the memory which will be recalled when the appropriate FADE button is next operated. If, however,
USE TIME is also selected and the memory concerned has a recorded Wait time, this Line changes to show the fade type and memory number, followed by a countdown of the remaining Wait time. For example:

4.9.5.1 Manual Fades
If a fade is under Manual control, both fade times appear as '<MAN>'. As in the case of fades which are stopped, if another fade is started, a Manual fade will disappear from the display, as control of this fade is no longer possible.

4.9.5.2 Fading Combined Memories
When fading single memories, the prefix (or the lack of a prefix) in the keypad window determines the 'type of fade' display (i.e. 'X', 'M' or 'D') and the active memory number appears without a prefix. If memories are combined before fading, however, the 'type of fade' is determined by the prefix to the first number selected and the active memory number is that which was shown in the keypad window at the moment the fade was started; no prefix is shown, however.

4.9.6 Channel Control Status Display
Under the heading 'CHANNEL' are displayed the store to which the Channel Control is routed (e.g. 'OUTPUT', 'SUB A', etc.); the number and level of the last channel controlled; the numbers of the last two channels controlled before that; and a display giving the current setting of the channel control wheel.
For example:

The symbol '>' indicates THRU and the above display therefore shows that channels '15 THRU 27 + 43' were selected as a group. Their levels were then increased by 50% so that the current level of channel 43 is 90% of full.
As each new channel selection is made, the number is added at the top of the list and those already displayed move down to make room. When numbers are being entered, the top line duplicates the information in the keypad display window (including any prefix).
When the level of the selected channel is adjusted using the wheel, the '<WHEEL>' display shows the extent of the change (as a percentage of full level) and the line below the heading shows the absolute level of the last selected channel.
When the '@' button is used to change the channel level, the '<WHEEL>' display will show the extent of the change only if the '+' and '-' are used to prefix the level entry (see section 4.2.3). If several adjustments are made, using both the ,@, button in conjunction with the '+' and '-' keys and the fader wheel, the '<WHEEL>' display shows the combined result of all the changes. If, however, an absolute level is entered using the '@' button, the '<WHEEL>' display is set directly to the level entered.
Only the line below the heading is affected when channel levels are adjusted. The remaining channel lines show only the channel number.
When memorised groups. of channels are selected, the memory number is
shown with the prefix 'G', preceded by '+' or '-' if appropriate.
As there is no single channel selected for which an absolute level can be shown, the level display shows the percentage change. For example:

If memories are recalled using channel controller Move mode the memory number is given the prefix 'M' (preceded by '+' or '-' if appropriate). The proportion of the fade which has been carried out is shown beside the memory number, and the extent of the last change on the '<WHEEL>' display. For example, if memory 85.7 is added to the current lighting as a Move-fade and 53% of the fade is performed using the wheel, followed by a further 20% using the '@' button, the display will appear as follows:

4.9.7 Output and Sub-master Displays
These two displays are each selected automatically when the corresponding Channel Control keypad mode is selected. In both cases, the top section of the screen shows, in tabular format, up to 180 of the channels controlled by the system. For example, channels 1 to 3 appear as follows:

The levels are shown as a percentage of full as in the LEVEL window on the desk, with full level appearing as 'F'. Any channel being modified in the selected store by the Channel Control has its number and level shown in reverse video, while any channel which has been modified since the CLEAR key was last operated has the colon between the number and level in reverse video. Channels which are at zero and not currently being modified appear at reduced brightness with no level shown.
In the case of the Sub-master display the screen shows the contents of the selected Sub-master store.

4.9.8 Memory List
The Memory List display is selected by operating the 'MEM LIST' button above the CHANNEL CONTROL keypad. Note that this does not affect the current Channel Control mode, the appropriate indicator remaining illuminated, and that the Output or Preset display may be reselected by operating the corresponding selection button.
The Memory List display gives a table, in numerically ascending order, of the memories, that have been recorded. One line is allocated per memory, and this includes recorded Fade times, Wait times and Links. In addition, the numbers of any effects which start or stop on recall of the memory concerned.
Note: Only one effect number is shown under 'START EFFECT' and one under 'STOP EFFECT'. If several effects are started or
stopped by recalling the memory, only the first (in numerical order) is shown, a plus sign ('+') following the number indicating that this is not the only effect concerned.
The Memory keypad is used to set the first number to be listed and all subsequent recorded memories are then displayed. Further pages
of the list may be viewed by pressing the PAGE button.
Example:

etc...

Following the list of memories is a list of Effects. As in the case of memories, one line is allocated per effect, and this includes additional information: Effect Type, Step Type, Next Effect number (link), Start Memory and Stop Memory.

Example:

etc...

4.9.9 Patch Display
This display is described in section 4.4.

4.9.10 Page
The 'PATCH' and 'MEMORY LIST' displays will often include more information than can be shown on the Video Mimic screen. The display will then be split into 'pages' which may be viewed by operating the PAGE button. Pressing the button steps the display to the next page, returning to page 1 after the last page.

4.10 FLOPPY-DISC UNIT
This unit may be provided to allow the data recorded in the system memory to be transferred to a removable 3.5'1 micro-floppy disc for Library storage. The discs may subsequently be reloaded and the data transferred back to the Gemini Memory.

4.10.1 Discs

4.10.1.1 Disc Specification

SHUGART SA130 SINGLE DENSITY DISKETTE SINGLE SIDED 3.5 INCH SOFT SECTORED

NOTE: Only the above discs, or a Rank Strand approved equivalent should be used, as inferior discs may cause excessive wear of the drive mechanism and heads.

4.10.1.2 Disc Care
The discs recommended are of the highest quality. However, due to the delicate nature of this medium, care is necessary to ensure that they are not damaged when handling. To guard against premature disc failure and excessive disc errors, the following precautions should be taken:
i) Return the disc to storage immediately it is removed from the drive mechanism.
ii) Do not Lay discs horizontally or stand things on them.
iii) Keep discs away from food, Liquids, grime or cigarette smoke.
iv) Do not expose discs to strong magnetic fields, e.g. by laying them on top of a Loud-speaker, or a T.V. monitor or VDU.
v) Do not subject discs to heat or direct sunlight.
vi) If the information stored on the disc is particularly valuable, or the disc likely to be heavily used, record a second copy as a back-up.
vii) Ensure that discs, once recorded, have the write protect tab set to the Safe position, i.e. with the small window in the corner of the disc pack open. This will prevent the recorded memories being overwritten.
viii) Ensure that the drive mechanism is regularly maintained, and is not subjected to excessive dirt.
ix) Never touch the disc surface, or attempt to open a disc.

4.10.1.3 Loading a Disc
Discs must be loaded into the drive mechanism with the identifying Label facing away from the ejection button and with the metal cover entering first; the disc Latches into place. The disc transfer may now be actioned.
The disc should never be ejected while the disc is being accessed, I as this may cause disc damage or data corruption. A red indicator on the Disc Unit Lights to show that it is in use.

4.10.2 Disc Operations
Disc operations are controlled by the MEM-DISC and DISC-MEM buttons above the MEMORY CONTROL keypad. These functions are clearing and initiaLising a disc, ~nd transferring some or all of the memories from system memory to disc or from disc to system memory.
The disc unit checks the validity of the data it reads, and attempts to correct any errors it Locates. If the problems cannot be overcome, error messages are displayed on the VDU.

4.10.2.1 Disc Clear and InitiaLisation
Before a new disc may be used to store memories, it must first be erased and formatted. The write protect on the disc should be set to the Write position; then Load the disc into the drive and insert a key (TOK 4) into the Record Lock keyswitch. Turn the key clockwise against the spring to the CLEAR position and then press the MEM-DISC button. The MEM-DISC indicator and the indicator on the Disc Unit Light to show that the disc initialisation is in progress.
Discs which have been previously recorded may be erased in exactly the same manner. It is only possible to completely re-initialise a disc - memories cannot be selectively erased; care must therefore be taken to ensure that none of the recorded data is still required. Data cannot be retrieved once the initialisation sequence has commenced.
A disc which has its Write Protect tab in the Safe position, i.e. with the small window in the corner of the disc pack open, cannot be cleared, and a 'DISC SAFE' error message will be given on the VDU.
If the indicator on the Disc Unit flashes during the initialisation process, this indicates a faulty disc which should not be used.

4.10.2.2 Copying Memories from Memory to Disc
Any memory or range of memories may be copied onto disc, and if required, this may include the Channel-to-dimmer Patch information.
The procedure for copying memories from the system memory onto disc is as follows:
1) Insert a disc into the drive. Ensure that the disc has been initialised and that the Write Protect tab is in the Write position.
2) Select the memory number or, using the THRU button, the range of numbers on the MEMORY CONTROL keypad. If memory 0 is included, the Channel-to-dimmer Patch information will be copied in addition to the memories.
3) Press the MEM-DISC (Memory to Disc) button to initiate the disc action. The associated indicator and that on the Disc Unit illuminate to show that the disc action is taking place.
A second operation of the MEM-DISC button, while the adjacent indicator is illuminated, will cause the disc action to terminate once the current memory has been copied.
Any state read from the memory will over-write the state which has the same number on the disc. If a range of memories is being copied, only those cues which exist in the memory will be over- written on the disc; cues which are recorded on the disc, but not in the memory will not be erased during the disc action. If no cues in the defined range are found in the memory, an error message is given on the Video mimic.
Note: A lighting plot saved on disc will normally be recalled in its entirety for modification, the revised version of the complete plot being saved on disc again. If the same disc is to be used to store the revised version, the disc concerned should be re-initialised before re-saving. If this is not done, any memories which have been deleted will remain on the disc and could be recalled in error when the plot is next used.
It should be noted that the time taken for the memory to disc action is rather longer than the time to transfer from disc to memory, as each memory is checked for errors after writing.

4.10.2.3 Copying Memories from Disc to Memory
The procedure for copying of memories from disc to memory is similar to that for memory to disc, the DISC-MEM button being used to initiate the disc action. Note, however, that the Memory Lock keyswitch must be in the OPEN position for the action to take place.
Any memory read from the disc will over-write the cue which has the same number in the Gemini memory. If a range of memories is being copied, only those cues which exist on the disc will be over-written in the memory; cues which are recorded in the memory but not on the disc will not be erased during the disc action. If no memories in the defined range are found on the disc, an error message is given on the Video mimic.
As in the case of Memory to Disc, a second operation of the DISC-MEM button while the adjacent indicator is illuminated will cause the disc action to terminate once the current memory has been copied.
As the memories are written into the Gemini memory, the 'LAST REC' number on the top line of the Video mimic display is updated, showing the last memory to be recorded.

4.10.2.4 Saving Special Effects on Floppy Disc
Special Effects prepared on the optional Programmable Effects Panel also may be copied to and from disc. The appropriate procedures are described in Chapter 6.

4.11 PRINT
If required, a printer may be connected to the Gemini desk to provide the operator or lighting designer with a paper record of the lighting states which have been recorded; of the Channel-to-dimmer Patch; or of the special effects prepared on the Programmable Effects Panel (if fitted).

4.11.1 Preliminary
Before starting to print, the following should be checked:
1) Ensure that the Printer has power available and that it is connected to the Gemini desk.
2) Check that there is sufficient paper.
3) Switch the Printer on and check that the POWER indicator illuminates.
4) Ensure that the paper 'top-of-form' is correctly adjusted. If this is not done, the Printer may print across the perforated folds in the paper.
The correct setting is with one of these perforated folds just above the print head. If the setting is incorrect, the paper may be advanced one line at a time by pressing the LINE FEED button; the printer must be set Off Line for this to be done. Operating the FORM FEED button will cause the paper will feed continuously until the current Top-of-Form is reached. When the paper is correctly adjusted switch the printer Off and then On again.
5) Check that the ON LINE indicator is illuminated. If not press the adjacent ON LINE button.
Further details regarding the above may be found, together with instructions on how to insert paper, change the ribbon, etc., in the handbook supplied by the Printer manufacturer.

4.11.2 Printing Memories
Memories are printed by entering a single number or a range of numbers (using the THRU button) on the MEMORY CONTROL keypad and then pressing PRNT (Print). The indicator adjacent to the PRNT button illuminates while the print action is in progress.
The printout starts with a list of the memories in the same format as on the 'MEMORY LIST' mimic display, i.e. including fade type, Fade and Wait times and Link. This is followed by the memories themselves, again in the same format as on the Video Mimic. Each memory starts on a fresh sheet of paper.

4.11.3 Printing the Channel-to-dimmer Patch
If memory number 0 is entered, or if memory 0 is included in a range of memories, the Channel-to-dimmer patch will be printed.

4.11.4 Printing the Special Effects
This is described in Chapter 6 - Programmable Effects Panel.

4.11.5 Stopping the Printer
A Print action may be stopped by operating the PRNT button a second time; i.e. while the associated indicator is illuminated. The Print action will not stop immediately, because the system works by filling a buffer store in the Printer which then prints the stored information automatically. Only when all the buffer store contents have been printed will the Print action end.
Once it has been stopped, the Print action cannot be restarted without reselecting the Print facilities required.