Punch 40DSM no output on either channel - diyAudio
Go Back   Home > Forums > General Interest > Car Audio

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 23rd June 2010, 02:36 AM   #1
diyAudio Member
 
Join Date: Sep 2009
Location: Wisconsin
Default Punch 40DSM no output on either channel

What is the best way to attack these amps. Right now I have no output on either channel, but I have a clean signal leaving the input board. I pulled the output fets so I wouldn't have to worry about them shorting. I did find one transistor shorted on the driver card, believe it was a PNP (3B) BC856. Could a 2G transistor be sub'd for this?

I have two of these amps and both have the same problem. The 10uF caps have all been changed, if they needed it or not.

cory
  Reply With Quote
Old 23rd June 2010, 04:26 AM   #2
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
The MMBTA56 should be a good sub.

With the outputs out of the circuit, you can't do much troubleshooting of the audio section with the amp powered up. Do you have a clean signal on pin 1 and no signal on pin 2 of the left channel and the reverse for the right channel?

Beyond that, virtually everything is in the feedback loop and depends on the feedback from the outputs to determine the voltage on the various components.

The attached images show the most common components to fail on the driver boards (assuming that you have this version of the driver boards).
Attached Images
File Type: jpg punchdsm01.jpg (36.9 KB, 69 views)
File Type: jpg punchdsm02.jpg (19.4 KB, 67 views)
  Reply With Quote
Old 23rd June 2010, 01:02 PM   #3
diyAudio Member
 
Join Date: Sep 2009
Location: Wisconsin
I have a clean signal for both channels, took me forever to figure out one channel fed into pin 1 and the other to pin 2.

The transistor in the upper right had failed shorted. I will put the outputs back in, and look for other problems.
  Reply With Quote
Old 24th June 2010, 04:14 PM   #4
diyAudio Member
 
Join Date: Sep 2009
Location: Wisconsin
Messing around in paint with the pics Perry posted, I am mapping the input signal from pins 1 and 2.

If this turns out to help I will do the same for the output side.

What is W3, dual transistor? I can't find any data on it.
Attached Images
File Type: jpg DSM Both.JPG (198.7 KB, 52 views)
  Reply With Quote
Old 24th June 2010, 05:04 PM   #5
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Paint should be outlawed. Download Open Office (free). It has a 'Draw' application that's infinitely better than Paint.

Email me before you do any more on this board.
babin_perry@yahoo.com
  Reply With Quote
Old 24th June 2010, 06:21 PM   #6
diyAudio Member
 
Join Date: Sep 2009
Location: Wisconsin
Sent an email.

I use Gimp normally, used open office prior to getting MS Office for a class.
  Reply With Quote
Old 24th June 2010, 09:19 PM   #7
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Is the TOC line going to -15v on the audio driver board?
  Reply With Quote
Old 25th June 2010, 02:19 AM   #8
diyAudio Member
 
Join Date: Sep 2009
Location: Wisconsin
The 40 has +-12 supplies and yes it is going to -12(pin4).

The swf file uses shockwave? I have just used windows explorer to see it, not sure if I am missing anything by doing this.
  Reply With Quote
Old 25th June 2010, 02:41 AM   #9
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Generally, you'd use your internet browser.
  Reply With Quote
Old 25th June 2010, 03:13 AM   #10
diyAudio Member
 
Join Date: Sep 2009
Location: Wisconsin
Any logic in removing the protection diodes? I have done this in the past to eliminate that part of the circuit. It looks to be D112 and D109?
  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
Output FETs for a Punch 150hd kevlar129bp Car Audio 34 26th February 2010 08:56 PM
Punch 200DSM output clipping 17DoubleE Car Audio 4 16th October 2009 12:30 AM
Selling a punch 250a2, old punch 75, and ppi epx 205 on EBAY ppia600 Swap Meet 0 23rd February 2008 01:17 AM
My experience: the cheap punch set VS Greenlee punch vax9000 Tubes / Valves 5 21st July 2006 07:52 PM
One channel has VERY faint output jjdche Car Audio 4 18th March 2004 04:22 PM


New To Site? Need Help?

All times are GMT. The time now is 03:16 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