Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Early B&W and Projection TV

Notices

We appreciate your help

in keeping this site going.
 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #11  
Old 03-12-2010, 11:34 PM
bandersen's Avatar
bandersen bandersen is offline
RCA 741PCS
 
Join Date: Mar 2009
Location: Chicago, IL
Posts: 8,821
Audio problem persists

I've got the video rock solid on this set but still no audio
All I get is static which does increase with the volume control. I can also touch the volume control wiper and I get a hum. I've gone over the audio IF stages pretty thoroughly, so I decided to try aligning it by following these instructions:



Here's the gear I used. A 3 AAs soldered together for the -4.5v AGC bias voltage. An EICO 232 VTVM and a Hickock 615 sweep and marker generator. Finally, an HP 45600B scope and demodulator probe.


I think I did everything correctly. Here's the ratio detector response curve, but still no audio Just a buzz that occurs when bright white portions appear in the video.
I know it's backwards, but I think that's just the nature of my sweep generator / scope - the key points match up more or less.


Any ideas ? I bet it's something really stupid!
__________________
Here are my Vintage Radio & TV YouTube Channel and Photo Gallery

Last edited by bandersen; 03-12-2010 at 11:55 PM.
Reply With Quote
 



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 05:45 PM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2026, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.