Perplexed by 5AR4 Tube Socket? Picture Included - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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 26th September 2005, 08:32 PM   #1
diyAudio Member
Join Date: Mar 2005
Location: USA
Question Perplexed by 5AR4 Tube Socket? Picture Included

Guys, can you help me out? I unearthed a terribly dusty, but nice Pilot EL84 Push Pull Integrated Amplifier. It's missing the rectifier tube and as you can see in the picture, the socket is clearly marked GZ34/5AR4.

I have a 5AR4 tube but it does not fit in the tube socket. The key is too large in the center of the tube to fit. Did they make different socket bases for this tube, or am I completely missing something here?


Click the image to open in full size.
  Reply With Quote
Old 26th September 2005, 08:38 PM   #2
Yvesm is offline Yvesm  France
diyAudio Member
Yvesm's Avatar
Join Date: Jul 2004
Location: Ardeche
Remove the base of the old broken tube wich is still in the socket !
  Reply With Quote
Old 26th September 2005, 09:08 PM   #3
diyAudio Member
Join Date: Dec 2004
Location: Mt Pleasant Sc
Default 5AR4

That is not the base of an old tube, that is an octal plug. However the result is the same, just pull it out and then you can plug the 5AR4 in the socket.
By the way looking at the condition of the amp, I would bring the voltage up with a variac and check B+ voltage as you bring the variac up very slowly.
No variac, then wire a lamp in series with the line cord to the amp and start with a 15 w bulb and work up to a 100w and see if everything is ok before you hook the amp directly to ac while monitoring B+ voltage.
Hope this helps
  Reply With Quote
Old 26th September 2005, 09:41 PM   #4
SY is offline SY  United States
On Hiatus
SY's Avatar
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 2
It is possible that someone soldered in some silicon diodes, then stuck the plug on there to prevent a tube from being inserted. Take a look underneath before plugging in a new GZ34.
"You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is."
  Reply With Quote
Old 26th September 2005, 10:04 PM   #5
diyAudio Member
Join Date: Mar 2005
Location: USA

Damn, you guys are good!!! Many thanks for the excellent posts.

SY, you are a very smart guy. I had popped the bottom cover and did not even notice the tiny diodes soldered across the rectifier socket.

Okay, time to dig out the variac and hope this girl does not like to smoke!
  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
Rectifier tube 5AR4 vs. 5U4GB? Ty_Bower Tubelab 51 25th April 2017 02:41 AM
Does anybody know anything about this amp? STUDIOCRAFT F1 (see picture included) dean ashmore Solid State 0 16th November 2008 08:08 AM
5AR4 Tube trade IFixAudio Swap Meet 0 28th January 2007 08:41 AM
Help on tube socket dung0981 Tubes / Valves 6 5th August 2006 08:31 AM
Tube socket wanted. (help where) Hojvaelde Tubes / Valves 3 21st June 2005 11:29 PM

New To Site? Need Help?

All times are GMT. The time now is 02:27 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