Welcome To the Hoffman Amplifiers Forum

September 07, 2025, 08:41:00 am
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: 2e30 tube  (Read 1961 times)

0 Members and 1 Guest are viewing this topic.

Offline gja

  • Level 1
  • *
  • Posts: 9
  • I love Tube amps
Hoffman Amps Forum image
2e30 tube
« on: June 03, 2020, 08:02:42 am »
Hi everyone,

Sorting out my stuff I found 4 x 2e30 tubes which I salvaged from a radio found in  a dustbin .
Can’t remember what the rest of the tubes were because it was all rusty so I just kept the tubes.

They are 7 pin sockets so before I actually buy the sockets andtry anything with them I was wondering if anyone had any experience, thought I’ d try them in a self split el84 amp which I like a lot.

Any thoughts?

Cheers

Offline DummyLoad

  • SMG
  • Level 5
  • *****
  • Posts: 5791
Hoffman Amps Forum image
Re: 2e30 tube
« Reply #1 on: June 03, 2020, 09:17:44 am »
at first glance, they seem similar to the US 6AQ5/6005 - except that they have a heater center tap. 6AQ6/6005 use pin 1 & 7 for control grid - the 2e30 uses pin 7 for the heater center tap.

if you decide to try and install them in an amp built for 6AQ5/6005 you need to make sure that amps' pin 7 are NOT wired as a control grid. 

for a new build, graft them into any plan that uses 6AQ5/6005 and you shouldn't have any issues - i wouldn't try to bias them as EL84s. 


--pete

Offline PRR

  • Level 5
  • *******
  • Posts: 17082
  • Maine USA
Hoffman Amps Forum image
Re: 2e30 tube
« Reply #2 on: June 03, 2020, 05:00:40 pm »
> similar to the US 6AQ5

Note no uni-potential cathode. This complicates biasing and heating, so much it hardly makes sense.

The real-good application is the original: a mobile transmitter. Can idle cold and heat-up fast on PTT.

https://frank.pocnet.net/sheets/096/2/2E30.pdf

Offline DummyLoad

  • SMG
  • Level 5
  • *****
  • Posts: 5791
Hoffman Amps Forum image
Re: 2e30 tube
« Reply #3 on: June 03, 2020, 06:23:25 pm »
Note no uni-potential cathode

i missed that. directly heated, ugh! no need to wonder why there's a CT for the heaters. otherwise electrically it does seem to favor the 6AQ5.

--pete

Offline gja

  • Level 1
  • *
  • Posts: 9
  • I love Tube amps
Hoffman Amps Forum image
Re: 2e30 tube
« Reply #4 on: June 04, 2020, 12:12:34 am »
Thanks for your posts, true I forgot about the cathode part...

I’ll keep them for some future, or sell them if anyone’s interested.

Thanks again!

 


Choose a link from the
Hoffman Amplifiers parts catalog
Mobile Device
Catalog Link
Yard Sale
Discontinued
Misc. Hardware
What's New Board Building
 Parts
Amp trim
Handles
Lamps
Diodes
Hoffman Turret
 Boards
Channel
Switching
Resistors Fender Eyelet
 Boards
Screws/Nuts
Washers
Jacks/Plugs
Connectors
Misc Eyelet
Boards
Tools
Capacitors Custom Boards
Tubes
Valves
Pots
Knobs
Fuses/Cords Chassis
Tube
Sockets
Switches Wire
Cable


Handy Links
Tube Amp Library
Tube Amp
Schematics library
Design a custom Eyelet or
Turret Board
DIY Layout Creator
File analyzer program
DIY Layout Creator
File library
Transformer Wiring
Diagrams
Hoffmanamps
Facebook page
Hoffman Amplifiers
Discount Program


password