F5 Turbo Builders Thread - Page 300 - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs

Pass Labs This forum is dedicated to Pass Labs discussion.

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 February 2014, 08:23 PM   #2991
diyAudio Member
 
Join Date: Dec 2005
Location: São Paulo
I shortly applied forward bias between the gate and source of one of my jfets, and left drain floating, during some idss measurement. Fortunately my psu was current limited at 15mA. It measures normally after that. Should I worry or am I good to go?

Thanks
Daniel

Last edited by Daniel(Del); 23rd February 2014 at 08:28 PM. Reason: spelling
  Reply With Quote
Old 23rd February 2014, 08:57 PM   #2992
Zen Mod is offline Zen Mod  Serbia
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
look in datasheet

if you didn't exceed max Ugs .........

if you did , even if just suspicious , it goes to bin

edit - I was thinking on mosfets

so , correction - if Jfet is alive , do not worry
__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM
  Reply With Quote
Old 23rd February 2014, 09:21 PM   #2993
diyAudio Member
 
Join Date: Dec 2005
Location: São Paulo
Quote:
Originally Posted by Zen Mod View Post
look in datasheet

if you didn't exceed max Ugs .........

if you did , even if just suspicious , it goes to bin

edit - I was thinking on mosfets

so , correction - if Jfet is alive , do not worry
Thank you ZM!
I was worried because k170/j74 datasheets list max gate current as 10mA. Since I was limited at 15mA, I thought they could become leaky or somewhat.
  Reply With Quote
Old 23rd February 2014, 09:30 PM   #2994
Zen Mod is offline Zen Mod  Serbia
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
I resumed that you tested them afterwards ;

what I meant - resuming that - if they're working , you're good
__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM
  Reply With Quote
Old 23rd February 2014, 09:59 PM   #2995
SRMcGee is online now SRMcGee  United States
diyAudio Member
 
SRMcGee's Avatar
 
Join Date: May 2004
Location: Wynnewood, PA
Quote:
Originally Posted by BobEllis View Post
Probably not the root cause of your problem, but trim the leads going into the soft start board so no bare copper is showing for safety.

I agree that it is likely a soft start failure.
Bob:

Is the fact that adjusting P1 and P2 each changed the positive and negative sides of each channel a red herring?

Regards,
Scott
__________________
Good decisions are derived from experience; experience is derived from bad decisions.
  Reply With Quote
Old 23rd February 2014, 10:02 PM   #2996
6L6 is offline 6L6  United States
diyAudio Member
 
6L6's Avatar
 
Join Date: Oct 2010
Location: Denver, Colorado
Quote:
Originally Posted by SRMcGee View Post
Is the fact that adjusting P1 and P2 each changed the positive and negative sides of each channel a red herring?
Yes.

When the two pots get into their adjustment range, it will feel like one of them is more directly adjusting the bias (of both sides) and the other is adjusting the DC offset.
  Reply With Quote
Old 10th March 2014, 07:31 PM   #2997
sts9fan is offline sts9fan  United States
diyAudio Member
 
Join Date: Apr 2006
Location: MA
Finally making progress on my V2. I know these diodes are not recommended but I had them and the PS boards could use them. Am I ruining my amp?!?
Click the image to open in full size.
  Reply With Quote
Old 10th March 2014, 07:51 PM   #2998
Zen Mod is offline Zen Mod  Serbia
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
theз are looking big enough

besides that , I can't see more from picture

__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM
  Reply With Quote
Old 10th March 2014, 07:59 PM   #2999
sts9fan is offline sts9fan  United States
diyAudio Member
 
Join Date: Apr 2006
Location: MA
They are the same MUR from the amp section. I thought I had read that the fast recovery were not ideal for this sort of PS.
  Reply With Quote
Old 10th March 2014, 08:20 PM   #3000
diyAudio Member
 
duder1982's Avatar
 
Join Date: Jan 2012
Location: Nebraska
Quote:
Originally Posted by sts9fan View Post
Finally making progress on my V2. I know these diodes are not recommended but I had them and the PS boards could use them. Am I ruining my amp?!?
Click the image to open in full size.
Keep the build process coming, I am using the same ps boards, and want to see how your amp turns out.
__________________
If I cant build it or fix it I really dont want it.
  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
F5 Turbo Circuit Boards chchyong89 Pass Labs 2363 27th September 2014 03:10 PM
B1 builders thread Bas Horneman Pass Labs 696 14th July 2014 01:57 PM
F5 Turbo is posted Nelson Pass Pass Labs 635 6th April 2014 11:51 AM
F5 turbo problems Rob Dingen Pass Labs 17 11th January 2013 09:38 PM
F5 Turbo ............. if only !!!!!! a.wayne Pass Labs 23 21st January 2012 03:24 AM


New To Site? Need Help?

All times are GMT. The time now is 11:30 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