7027a testing - 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 8th August 2011, 03:49 PM   #1
diyAudio Member
 
Join Date: Aug 2011
Default 7027a testing

Just arrived here and left a short introduction. Looks like a great forum.


This is my question: When I'm out checking on possible tube buys I take my little EMC 213 tester with me for quick quality and short checks before buying. Problem I have is there are no settings listed for 7027/7027a tubes. They will not test properly on 6L6 setting, I assume because of the 2 extra pins. Can someone tell me what those settings would be or where I could find them? I'm having no luck at all..thanks..bruce
  Reply With Quote
Old 8th August 2011, 09:23 PM   #2
diyAudio Member
 
Join Date: May 2005
Location: California
7027 is electrically the same thing as a 6L6 but has higher voltage / dissipation ratings. You are right about the two pins, that is probably giving you troubles on testing. They would be pins one (1) and six (6). If you have a tube tester that you can select what the different pins of the tube under test see, make sure pins 1 and 6 are NOT connected to anything. Then it should test like any other glass 6L6. The other thing you can do is cut pins 1 and 6 off of the 7027 and then it will test correctly on the 6L6 setting. This will devalue the tube though.
Daniel
  Reply With Quote
Old 8th August 2011, 10:06 PM   #3
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Dan, specifically, it's a slightly re-pinned version of 6L6GC. One can rig up an adapter socket to use it in 6L6 tests or amplifiers.
__________________
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 9th August 2011, 01:05 PM   #4
diyAudio Member
 
Join Date: Aug 2011
SY..could you tell me how to do that?
  Reply With Quote
Old 9th August 2011, 01:42 PM   #5
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Sure. Get yourself an octal plug and an octal socket. Using a relatively stiff wire, you can connect the two, with the socket floating about 1 cm or so above the plug. Care must be taken when plugging and unplugging! If you're a real studboy, you'll find some high voltage potting material and make it into a monolithic assembly which will be considerably less fragile.
__________________
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 9th August 2011, 02:23 PM   #6
diyAudio Member
 
Tom Bavis's Avatar
 
Join Date: Jun 2002
Location: Macedon NY
In most cases, 7027 and 6L6GC are interchangeable. Amps with 7027 seldom used pins 1 and 6 (but check!). 6L6 amps may have used pins 1 and 6 as tie points - move these wires to a new terminal and either will work. I don't have an EMC tester any more, but I believe it has a switch corresponding to each pin. Set for 6L6, set switch #6 to the same position as #5, set switch #1 to the same position as #4, and test. Pins 1 and 6 may test "short" - ignore.
  Reply With Quote
Old 14th August 2011, 01:52 PM   #7
diyAudio Member
 
Join Date: Aug 2011
Thanks Tom that worked perfectly!
  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
Started work on my stereo 7027a PSE amp 807tubenut Tubes / Valves 7 23rd January 2011 09:51 PM
Looking for PP 7027a shematic 807tubenut Tubes / Valves 1 21st August 2010 08:52 PM
7027A with tubelab simple se pforeman Tubelab 10 8th November 2009 03:48 PM
testing, testing 123 neil_kaye Full Range 0 25th December 2005 09:21 PM
WTB 7027A Tubes webercarbmann Swap Meet 0 24th November 2002 10:37 PM


New To Site? Need Help?

All times are GMT. The time now is 04:30 PM.


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