Kustom 250 amplifier, well done - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 20th May 2004, 05:57 PM   #1
Lenny is offline Lenny  United States
diyAudio Member
 
Join Date: May 2004
Location: New Hampshire
Default Kustom 250 amplifier, well done

Hi there
I'm working on a model 250 amplifier that came into our shop for repair.
The customer reported that the unit smoked when it was powered up. So far I
have found the following defective components:
1. Q4, Q5, Q8, Q9, drivers open
2. R35, R25, .51 ohm resistors open
3. Q12, Q13 output transistors shorted
4. R27, 681 ohm base resistor for Q7 open
This seems to be an an inordinate amount of component failures in this unit. I've never seen all the drivers on a unit open. Is this a usual occurance on this model?
Also, are these parts still available or can I substitute?
Some other questions; Can I get away with just replacing the two shorted
outputs or should I change them all? Is it critical that these outputs and
the drivers are matched and how tight is the spec on that 681 ohm resistor?
I have checked everything else on the output board and have not found any other problems as of yet however I was wondering if given what I've already mentioned, its felt that I've covered all the bases, or might there be other things I should look at as well?
One other thing: I'm having trying to find replacement outputs and drivers. The outputs are 4 RCA 36892's and the drivers are 2 RCA 38737's and 2 RCA 38736's. All were probably matched I'm assuming.
Anyone know where I might find any of these? Thanks very much for any help and advice.

Lenny Stein, CET.
Barlen Electronics
465 Derry Road
Chester, N.H. 03036
Tel: 603-887-4253
  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
Kustom Amplifier Speaker Identification tekniderm Instruments and Amps 4 20th June 2006 12:22 AM
Wanted: DIY amplifier builder with experience. I need a 0.7 ohm stable amplifier Audiophilenoob Swap Meet 34 16th May 2005 11:58 PM
Kustom BassIII distortion Netlist Solid State 6 30th May 2004 08:11 AM
Questions about how to decrease the PASS A-40 amplifier into a class AB amplifier. novtango Pass Labs 2 21st October 2002 01:50 AM


New To Site? Need Help?

All times are GMT. The time now is 03:00 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