As long as your DVR features a composite monitor
output for playback then all you need to do is loop the video
through the VCR, for example Monitor Output to VCR IN, VCR OUT
to Monitor IN. Whatever you view on the system you can now record
on the VCR. If you're using a domestic VCR you may require a scart
to BNC cable.
The most common cause of this problem is the
synchronisation between the multiplexer and VCR. To generate fields
at the same rate ensure the recording times are the same on both
units, for example 24hours on the multiplexer and 24hours on the
VCR.
If this does not work then either a sync cable
or vext cable will be required. Multiplexers are designed with
sync or swipe pulse inputs. Many VCRs produce a synchronising
pulse at a connector at the back of the recorder. The pulse generated
by the VCR controls the rate at which the multiplexer switches
between cameras. Connecting this pulse to an input of the multiplexer
enables the multiplexer to send fields to the VCR at exactly the
right rate for the time lapse setting selected.