TCJ Cathode-Coupled Amplifier - 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 16th July 2007, 10:05 PM   #1
diyAudio Member
 
Join Date: Apr 2007
Default TCJ Cathode-Coupled Amplifier

Hello all...
I recently finished up my first tube project (a Bottlehead S.E.X kit)which turned out better than expected and I would like to move forward with a simplified scratch-built project. I thought I'd give John Broskie's "TCJ Cathode-Coupled Amp" a try.

Click the image to open in full size.

My initial plan is to use Edcor's XPWR104

with a pair of Tung Sol 5687s. Ok so far?
I feel confident that I can safely follow the schematic, but I have a question regarding the heater circuit. JB suggest referencing the heater circuit to +40 V. How do I do this? Does this mean that my heater circuit should be 40V-46.3V (low-hi)
Thanks

7/10
  Reply With Quote
Old 17th July 2007, 05:19 PM   #2
diyAudio Member
 
Join Date: Apr 2007
bump...
  Reply With Quote
Old 17th July 2007, 05:28 PM   #3
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
You've got the basic idea. Make a voltage divider between B+ and ground out of two resistors sized so as to draw a milliamp or two and for their junction to have about 40V on it. Bypass the lower one with an appropriate cap to ground (1-100uF).

If you're using DC heaters, attach the (-) end to the junction point at 40V.

You can do something a little trickier which will really suppress common-mode noise and that is to build your heater supply with two regulators, one +3 and one -3. The common point is then the one biased up.

The heaters should be locally bypassed for RF.
__________________
You might be screaming "No, no, no" and all they hear is "Who wants cake?" Let me tell you something: They all do. They all want cake.- Wilford Brimley
  Reply With Quote
Old 18th July 2007, 05:05 PM   #4
diyAudio Member
 
Join Date: Apr 2007
Sy,

Thank you...


7/10
  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
6T9 push pull with Cathode Coupled input Brit01 Tubes / Valves 5 18th January 2009 11:58 AM
Direct-coupled cathode/source follower driver in PP? ray_moth Tubes / Valves 83 17th July 2008 02:53 AM
cascode vs asymmetrical cathode coupled oldeurope Tubes / Valves 47 18th April 2008 04:37 PM
Help with a cathode coupled pentode driver? Svetlana Tubes / Valves 2 26th July 2006 01:06 PM
Cathode-coupled Phase Splitter Formula MelB Tubes / Valves 5 14th February 2005 08:51 PM


New To Site? Need Help?

All times are GMT. The time now is 09:46 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