Video System Trouble Shooting Guide - Videx VANDAL RESISTANT Technical Manual

TROUBLE SHOOTING
VIDEO SYSTEMS
SYMPTOM
No call tone, Videophone works only by
pressing the camera recall button.
Videophone rings but picture remains off.
Videophone red LED on but no picture
Picture poor
No Camera recall
Hum on the speech lines
No audio
No speech from videophone to door panel
PAGE 23 of 24 AUDIO/VIDEO VANDAL RESISTANT TECHNICAL MANUAL
TEST
Check the 13Vac on the Art.850 PSU
Check the wire from terminal T on the Art.890 is not
broken or short.
Try changing the Art.890
Check 24Vac on Art.850
Check jumper JP4 on the videophone is in position B
Check wires 1 & 6 are ok from the Art890 to the
videophone and 20Vdc is present during a call.
Try changing the Art890
Check coax cable is not broken or short
Check Art.894 is powering up with 12Vdc during a
call. Try taking the coax straight from the camera to
a videophone.
Check for 20Vdc across the camera terminals I & F1
during a call (powered from Art890)
Check all end of line resistors are fitted to unused
outputs on the Art.894 and a resistor is also fitted to
the end of line.
Check for any broken coax's or screens.
Check wire F1 & 6 is not broken and is not to small.
Wire TV1 broken
Try moving the wire from TV1 into T
Ensure all intercom cables do not run close to higher
voltage cables
Try another amplifier at the door panel.
Check terminals 3 & 4 for 12Vdc from the Art.890
Check terminal 5 from
videophones is not broken.
Check terminals G2 and 4 on the Art.890 for
continuity back to door panel and videophone.
the Art.890 to the
VER1.1