Pentode C.F, where to connect the suppressor grid ? - 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
Thread Tools Search this Thread
Old 11th August 2014, 02:46 PM   #1
diyAudio Member
Tubologic's Avatar
Join Date: Dec 2004
Location: Brussels
Default Pentode C.F, where to connect the suppressor grid ?

I intend to use a triode-connected small power pentode (E80L) as a cathode follower for driving a 211 PP triode output stage. The E80L is a true pentode and has a separate suppressor grid (G3) connection which is usually connected to the cathode in most circuits. Now I'm wondering if it would be better to connect the suppressor grid to the cathode or the anode when used in a cathode follower configuration, and why ? (the screen grid G2 being tied to the anode for triode operation).
  Reply With Quote
Old 11th August 2014, 02:52 PM   #2
DF96 is offline DF96  England
diyAudio Member
Join Date: May 2007
If g2 is wired to the anode then g3 is no longer needed, as primary electrons and secondary electrons end up in the same place. It doesn't matter too much whether you connect it to the anode or cathode.
  Reply With Quote
Old 11th August 2014, 06:26 PM   #3
disco is offline disco  Netherlands
diyAudio Member
disco's Avatar
Join Date: Apr 2006
Location: Holland
Might the small interelectrode capacitance be of importance?
  Reply With Quote
Old 11th August 2014, 08:12 PM   #4
DF96 is offline DF96  England
diyAudio Member
Join Date: May 2007
In audio, for a CF? No.
  Reply With Quote
Old 14th August 2014, 08:29 AM   #5
RE 604 is offline RE 604  Germany
diyAudio Member
RE 604's Avatar
Join Date: Oct 2003
Location: Germany
.........the data sheet says "g2 on a and g3 on k" for triode operation .

Valvo Handbuch Spezialröhren 1966

Kind Regards ,
Alexander .
No reason to get excited : Jimi Hendrix .
  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
Pentode pre/compressor (warning nube attempt at circuit drafting) --suppressor grid Blue Jinn Tubes / Valves 33 18th August 2014 08:25 PM
grid stopper and grid choke on pentode input YouAgain Tubes / Valves 3 12th February 2012 09:32 PM
Beam pentodes and suppressor-grid pentodes of same type jon_010101 Tubes / Valves 3 2nd May 2009 11:18 PM
Pentode current sink - how to connect the control grid? ray_moth Tubes / Valves 4 20th December 2004 02:26 AM

New To Site? Need Help?

All times are GMT. The time now is 09:50 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