Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Pass Labs This forum is dedicated to Pass Labs discussion.

Nakamichi PA-7II won't power on, limiter resistor blown
Nakamichi PA-7II won't power on, limiter resistor blown
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 Today, 02:14 AM   #241
Chamberman is offline Chamberman  United States
diyAudio Member
 
Join Date: Jun 2001
Location: USA, Dallas/Ft Worth, Tx
Was that with the bias pot at the max? If so its not enough to turn them on.
__________________
KC
  Reply With Quote
Old Today, 02:28 AM   #242
tenelson is offline tenelson  United States
diyAudio Member
 
Join Date: Mar 2015
Location: Santa Fe, NM
It's the same kind of behavior as on the left channel, where the bias pot has no real effect on those voltages. Maybe the faulty transistors are pulling those voltages down somehow?
  Reply With Quote
Old Today, 02:31 AM   #243
Chamberman is offline Chamberman  United States
diyAudio Member
 
Join Date: Jun 2001
Location: USA, Dallas/Ft Worth, Tx
You sure that you do not have a broken wire going to the bias transistor or bias network on this channel?

It could be one of the driver transistors base junctions breaking down as well, but the fact both polarities are being loaded seemingly the same would imply a bias network issue in my opinion.
__________________
KC
  Reply With Quote
Old Today, 02:42 AM   #244
tenelson is offline tenelson  United States
diyAudio Member
 
Join Date: Mar 2015
Location: Santa Fe, NM
Jeez, I didn't even think to look at that. Sure enough, one of the wires to the bias transistor is broken. Fragile things. I'll repair it tomorrow and report back.
  Reply With Quote

Reply


Nakamichi PA-7II won't power on, limiter resistor blownHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Nakamichi PA-7 Power Transformer sourceoneaudio Swap Meet 6 25th March 2018 04:54 PM
Nakamichi PA-7II: Thermofuse in the potted transformer electrafixion71 Pass Labs 31 3rd January 2015 02:31 AM
Limiter Resistor of MOSFET Power Amp ervinl Solid State 11 23rd July 2010 06:55 AM
Nakamichi PA-7II manuals - HELP Peteb Pass Labs 4 4th October 2007 07:09 PM
Nakamichi OMS-7II help proteo01 Digital Source 0 17th September 2007 03:12 AM


New To Site? Need Help?

All times are GMT. The time now is 02:36 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Copyright ©1999-2020 diyAudio
Wiki