Videoswitch VCM - Manual (Page 8)

Duplex Multiplexers
User Manual Page 8
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Videoswitch
VCM614d.doc
3. Switch Options
3.1 Time Lapse Mode Switch (rotary) - with a Step Cable
The multiplexer may be used with a “step” cable connected to the VCR. The step cable allows the
multiplexer to detect the time-lapse recording mode of the VCR and configure itself automatically.
If a step cable is being used, the rotary switch (S1) must be set one of two positions:
Rotary
Switch
(S1)
“Step” Input
0 No pull-up resistor
(default)
1 With pull-up resistor
3.1.1 Reasons for using a step cable
a) If the required time lapse mode is not available by switch selection.
b) If there is any doubt as to the way in which the VCR samples.
c) If the time lapse mode is regularly altered (e.g. a different mode at weekends).
3.1.2 Configuring the system to use a STEP cable
a) Set the rotary switch (S1) to position 0.
b) Connect the step output (sometimes called “CAM SW”, “SW OUT”, etc.) of the VCR to pin 14
of the 25-way D-type connector on the multiplexer.
c) Set the VCR up to generate a step signal (if this is a menu programmable option). Also select “1
Field” mode (not “Frame”) if this is an option.
3.1.3 Check that the STEP cable is operating properly
a) Put the multiplexer into RECORD mode.
b) Make sure the VCR is in time-lapse RECORD mode (3-hour mode will not produce a pulse from
some makes of VCR).
c) Look at the top right corner of Monitor “A” to see if the correct time lapse mode is being
displayed (allow up to 5 seconds to detect the mode).
3.1.4 If the multiplexer is not detecting the correct time lapse mode
a) Check that the VCR is set to RECORD in a time lapse mode (e.g. 24 hour).
b) Check that the VCR has been programmed to generate the step pulses.
c) Try changing the setting of S1 to enable or disable the pull-up resistor for the STEP input from
the VCR.
Do a test recording to make sure that the all cameras are correctly recorded and replayed.