tllee 0 Posted June 22, 2010 the AV Tech AVC791A 4 Ch DVR, using normal VGA cable (3ft) got the 4ch screen, after i change to 5 meter (15ft) VGA cable the LCD screen don't display any thing, how to Solve this problem. thx dvr --> 3ft VGA Cable --> got screen dvr --> 15ft VGA Cable --> no screen dvr --> 3ft VGA Cable (got screen) change to 15ft VGA cable --got screen , after restart dvr, the 15ft vga cable don't have screen again Share this post Link to post Share on other sites
hammouda 0 Posted November 2, 2010 Hello, I faced the same problem with 798AD, there is no way to fix it (this is what I have been told by AVTECH (taiwan) technical team. Share this post Link to post Share on other sites
Soundy 1 Posted November 2, 2010 It's possible that cable doesn't have a connection required by the DVR to detect the presence of the monitor. Have you tried a different long cable? Have you checked that all pins are present and connected through? Share this post Link to post Share on other sites
tomcctv 190 Posted November 2, 2010 the AV Tech AVC791A 4 Ch DVR, using normal VGA cable (3ft) got the 4ch screen, after i change to 5 meter (15ft) VGA cable the LCD screen don't display any thing, how to Solve this problem. thx dvr --> 3ft VGA Cable --> got screen dvr --> 15ft VGA Cable --> no screen dvr --> 3ft VGA Cable (got screen) change to 15ft VGA cable --got screen , after restart dvr, the 15ft vga cable don't have screen again we had problems just like yours and we got around it by adding i vga extender box ............it gives the vga a little boost. Share this post Link to post Share on other sites