Aritech ATA-4/9 CSqX, Инструкция по установке и эксплуатации, Страница: 10 / 31

Installation and Operation Manual
0150-0147 1-6 Revision B
NOTE: In this manual, real-time mode is defined as 3-hour mode.
VEXT simplifies multiplexer operation by automatically synchronising the multiplexer to the VCR. The
VEXT signal is especially useful with VCRs having dual recording speeds (alarm and normal),
because it makes the multiplexer follow alarms.
The VCR sends a VEXT to the multiplexer whenever an image is recorded. The multiplexer then
transmits the next image to Video In on the VCR. In this way, the VCR controls the multiplexer’s
recording speed. The VEXT Pulse Edge can be set to trigger on either the positive-going or negative-
going edge. See Table 1-3 on page 1-8 for setting the Record Speed.
NOTE: Do not change the VEXT Pulse Edge setting without consulting Technical Support first!
The VEXT input accepts a TTL, field-synchronised, positive, or negative pulse.
Consult the VCR manufacturer’s instructions to connect:
This multiplexer jack: To this VCR location:
VEXT input wire (red) and ground wire (black). The appropriate VCR terminals.
NOTES:
Some time-lapse VCRs do not transmit a VEXT signal in real-time mode. This can still
work, but extra precautions will be required in the planning of your security system.
When the VCR switches to the alarm mode, there will be a loss of the VEXT signal from
the VCR. This will cause the multiplexer to stop outputting images for a few seconds
while it tries to determine if the recording speed of the VCR has been changed, or if the
pulse is completely lost.
If the pulse is determined to be lost, the unit will begin outputting images according to the
switch programmed settings.
To use such VCRs, select a recording speed on the multiplexer that matches the number
of images per second required by the VCR when it is in alarm. In these cases, be sure to
correctly setup VEXT in the VCR’s menus. Contact Technical Support if additional
assistance is necessary.
Monitor Connections
Use a 75-ohm coaxial cable to connect the unit's monitor output to the Monitor's IN connector. If you
are looping through the monitor, be sure to set the monitor’s termination switch to HI-Z. Also, make
sure that the last video device on the line has its termination switch set to the 75-ohm position.
Switch Settings
The tables below illustrate the possible settings for all programmable features of this unit.