World-Designs-Forum  

Go Back   World-Designs-Forum > WAD > WAD Problems
Register FAQ Members List Calendar Gallery Today's Posts Mark Forums Read

WAD Problems For questions and answers re older World Audio Design Projects

 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #1  
Old 24th March 2022, 12:41 PM
KennyK's Avatar
KennyK KennyK is offline
Senior Member
 
Join Date: Dec 2005
Location: Glasgow
Posts: 191
Default WAD Phono II problem

Hi All,

I'm trying to troubleshoot a problem with my WAD Phono II, which has been long upgraded with various boutique resistors/capacitors, and many PCB tracks have been hard wired for around 15 years

What started as a slight channel imbalance has got worse with the Left channel now virtually inaudible, so I've finally had a poke around with a meter.

I've got a couple of Low voltages on V3 Anode (pin 1) and V4 Cathode (pin 3) which are both stablising at 37v instead of 120v. On power up V3 pin 1 starts at 120, but as the heaters warm up the voltage pulls low. V3 Cathode (pin 3) seems high at 1.6v

The HT seems fine. without the Pre II connected, it's sitting at 270v instead of 250v
Any suggestions where to look?

Thanks
KennyK
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 +1. The time now is 07:27 AM.


Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright World Designs