Revox B126 CD Player Power Supply Troubleshooting Help Required - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 15th September 2010, 05:31 PM   #1
dtm1962 is offline dtm1962  Canada
diyAudio Member
 
Join Date: Apr 2003
Location: Sarnia, Ontario, Canada
Default Revox B126 CD Player Power Supply Troubleshooting Help Required

I have been repairing my B126 CD Player recently which has a problem on the Servo board, and I decided to take another stab at the repair.

I turned the unit on to make some measurements on the Servo board, I noticed the PS voltages were all wrong from the day before, so I decided to check the power supply itself and noticed the +5V & +10V & -5 & -10V supplies are now reading +0.2V (+5v) & +0.7V (+10V) ; -1.5V (-5V) & -1.5V (-10V).

Note this cd player has a standby power function as well which may complicate the troubleshooting

Refer to attached marked-up PS schematic pdf file for details.

Any help would be appreciated.

Thanks in advance,
Attached Files
File Type: pdf revox_b126_Power_Supply_001.pdf (78.4 KB, 29 views)
__________________
Dan
  Reply With Quote
Old 15th September 2010, 09:10 PM   #2
mjf is offline mjf  Austria
diyAudio Member
 
Join Date: Jan 2009
Location: Austria
hello.
can you test q2 /bc547.........(and perhaps q3 /bc557)...........perhaps they are damaged.
greetings
  Reply With Quote
Old 16th September 2010, 04:03 AM   #3
dtm1962 is offline dtm1962  Canada
diyAudio Member
 
Join Date: Apr 2003
Location: Sarnia, Ontario, Canada
Default Transistors Changeout

Since all the voltages on the base of the NPN & PNP transistors seem to be reversed, I am going to change out Q1 thru Q5 to be safe. I have checked the resistors as they seem to be OK but I will check again to be safe.

Thanks,
__________________
Dan
  Reply With Quote
Old 19th September 2010, 02:51 AM   #4
dtm1962 is offline dtm1962  Canada
diyAudio Member
 
Join Date: Apr 2003
Location: Sarnia, Ontario, Canada
I found that Q1 & Q5 opened as a result of the TCA0372 Power OPAMP in the Servo circuit shorted out.

I replaced TCA0372 & the 2 transistors and I am back to where I started with CDM4/27 that does not read the disk at all.

I will add details in other thread....
__________________
Dan
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Revox B126 CD Player Malfunction- Help Needed (TDA1541A-CDM4/27) dtm1962 Digital Source 14 16th October 2010 02:40 PM
Revox B-201 Remote: Will it work with a B-126 Revox CD Player dtm1962 Digital Source 2 3rd August 2010 02:20 AM
Revox B126 / B226 CD Player poynton Digital Source 0 6th March 2009 06:40 AM
Revox B226 B126 spares wanted poynton Swap Meet 9 31st March 2008 12:47 PM
Revox B226 cd player mevangel Digital Source 0 9th January 2003 04:32 PM


New To Site? Need Help?

All times are GMT. The time now is 05:35 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2