LME49810 biasing procedure temp comp and simple resistor - Page 3 - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Chip Amps Amplifiers based on integrated circuits

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
Thread Tools Search this Thread
Old 21st March 2013, 05:03 PM   #21
diyAudio Member
Join Date: Dec 2012
Location: BC,Canada
Default LM4702 biasing

Hello R.,
I bought a pair of LM4702 amps prebuild driving a single pair K1058/J162 ;one of the channel Voltage measuring across 0,22R is
30V (simple bias system ,just a VR 1K) instead of 20mV of other channels ;this value also found at the sink-source of its LM4702 .
I swapped it with a new LM4702 ,the initial voltage was 10 volt ,after
2 hours 6V ,VR at minimal setting .(still FAR from 20mV )
Help is needed ,please .
  Reply With Quote
Old 21st March 2013, 05:24 PM   #22
diyAudio Member
palstanturhin's Avatar
Join Date: Jun 2011
Let me understand...
You measured 30v across the .22 resistor?
In that case your .22R resistor must be faulty.
  Reply With Quote
Old 22nd March 2013, 03:29 PM   #23
diyAudio Member
Join Date: Dec 2012
Location: BC,Canada
Hi P.

Yes ,you are right ne of the 0.22R is faulty .I replaced both with a set
old surplus ,the K162 exploded .will report back one it 's corrected.
Thanks man.
  Reply With Quote
Old 23rd March 2013, 07:52 AM   #24
AndrewT is offline AndrewT  Scotland
diyAudio Member
Join Date: Jul 2004
Location: Scottish Borders
use a bulb tester.
regards Andrew T.
Sent from my desktop computer using a keyboard
  Reply With Quote


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
Simple SE Cathode Resistor Values skidave Tubelab 21 10th February 2016 11:50 AM
Simple opamp problem (biasing) - can you help? peskywinnets Solid State 29 29th March 2011 08:59 PM
Mystery resistor in simple audio amp MajorMajor Solid State 93 21st January 2010 08:29 PM
simple se cathode resistor question pforeman Tubelab 4 1st June 2009 05:08 PM
Normal temp of a 2 watt resistor? turbo_slug Parts 18 30th May 2008 11:25 PM

New To Site? Need Help?

All times are GMT. The time now is 04:22 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2