partial feedback stuff - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

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 14th January 2006, 12:24 PM   #1
diyAudio Member
 
Join Date: Mar 2005
Location: mid wales
Default partial feedback stuff

guys

refering to Broskies version of PF:

in his article he uses just a resistor
from 300B plate to before coupling cap
in effect the driver's plate
and gives the maths for calculating R

http://www.tubecad.com/march2001/page8.html

in t.rex he uses 47K followed by 2.2uf
from 300B plate to 300B grid

http://www.enjoythemusic.com/magazin.../trex/fig1.jpg

does anyone have an opinion as to why the two topologies
and
in the second instance how he calculated C

looking forward

dave dove
  Reply With Quote
Old 14th January 2006, 01:29 PM   #2
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
I get a 403 error from the second link.
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote
Old 14th January 2006, 02:17 PM   #3
diyAudio Member
 
Join Date: Mar 2005
Location: mid wales
SY

i just tried it and it works fine

try this:

http://www.blackdahlia.com/html/tip_50.html

dave dove
  Reply With Quote
Old 15th January 2006, 12:02 AM   #4
diyAudio Member
 
Join Date: Jul 2003
Location: Ann Arbor, MI
Hey-Hey!!!,
I have not read the article in question. I do use the general topology quite extensively in one form or another.

Make sure the provided math accounts for the plate Z of the driver tube. The plate resistance forms a voltage divider and the NFB amount is reduced.

Pentode drivers are excellent choices, and for the same reason, the cascode.

One can also do away with the driver stage voltage supply speerate NFB resistor, and go to a tap on the OPTx plate winding. This is the nuts and bolts to the E-Linear topology. I enclosed a basic PP schematic.
cheers,
Douglas
Attached Images
File Type: gif tinyelin2_poinz3.gif (5.5 KB, 160 views)
__________________
the Tnuctipun will return
  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
Partial Feedback EL84PP - Not quite as expected (yet) Svein_B Tubes / Valves 44 18th May 2008 05:59 PM
Partial feedback confusion Jeb-D. Tubes / Valves 4 22nd April 2008 06:20 PM
Partial feedback DHP SE amp Fuling Tubes / Valves 21 5th August 2005 10:20 AM
Partial Feedback Amplifiers audiousername Tubes / Valves 130 23rd May 2005 08:03 AM


New To Site? Need Help?

All times are GMT. The time now is 03:28 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