|
|
|
Re[6]: JVC av-27920
Robert Posted Jan 16, 2006, in response to:Eric
Hello
Yup checked that those to.Q702 4.78 volts,.1. At pin 2 4.5v. R708 both sides shows 4.78v. Pin 24 shows 2.12v. I have replaced two vertical ics
LA7832 just incase one was bad.Replaced c424 twice incase.From Q702 to pin 7
on la7832 .1.I agree with you the problem seems to be pin 7 of the vertical ic,
I do not have the 1.6v I should have but where to go from here I think is a little above my head.Just to make sure I am reading the schematics correctly,
the 1.6v is to come out of pin 7.If that is the case there is something wrong there.If the 1.6v is to come to pin 7 there may be a problem in the line that my meter is not capable of detecting.I will wait to hear from you,and thanks again. Rob
Reply
1 comment
Robert
The DC voltage at pin 7 of the Vertical Out IC is supplied by D421 and C424 from the 25V Supply. The waveform shown at pin 7 is supplied by the IC, as it assists the waveform at pin 3 (pump up). Do you have a way to check the input signal to the Vertical Out IC (Pin 4)? It should show as the Sams I sent you (1.5VPP). If the input waveform is okay, try to find a way to remove Q702 or R705 or if possible cut the trace feeding them with an X-Acto knife and see if the problem clears. I believe Q702 feeds V. Sync to the Micro for OSD.
Eric
Comment 1, Last comment
by Robert Jan 17, 2006
|
