1 valve radio with Russian sub-minature valves - UK Vintage Radio Repair and Restoration Discussion Forum

Neil Purling · 28th Jun 2014, 10:12 pm

I wondered how many people have used these Russian 'pencil' valves. There are several types of course, but I bought 1J24B. Has anyone built anything with these ?
It could have been an old circuit adapted to using the sub-minature valves.
What I have managed to establish is my choice of component is happiest with 45V HT.
What's right for the filament supply? I have goodness knows how many NimH AA cells.
They seem about 1.2V at full charge. I can't remember what the filament current drain is off-hand, but I can easily wire more AA cells in parallel.
I was wondering whether the Electron-Coupled design can be re-designed to use the Russian valve at 45V HT with regeneration by varying the screen voltage.

I have done stuff with conventional 6.3V pentodes like the EF39, but nothing with low-voltage valves. The DF9* series can be a bit pricy. I got the ten Russian valves for the same price as one DF91.

Cobaltblue · 28th Jun 2014, 10:19 pm

Michael Watterson over on VRAT has done a lot with these including replacing D series valves.

Just be warned he's very enthusiastic about the Russian Rod Pentodes

Cheers

Mike T

Neil Purling · 28th Jun 2014, 10:45 pm

Cobaltblue: I don't suppose that the person you named posts here too..........
VRAT won't allow you to even read the threads without registering. There's an interesting link to a circuit on another site, which you can't view for the same reason. I guess I would have a few questions for Mr Watterson.

brunel · 28th Jun 2014, 11:38 pm

They can all be read, without login in.

http://www.forum.radios-tv.co.uk/vie...entodes#p87618

Cobaltblue · 29th Jun 2014, 8:32 am

Quote:

Originally Posted by Neil Purling

Cobaltblue: I don't suppose that the person you named posts here too..........

He used to post here under the name Neon Indicator so it might be worth rooting out some of his old posts.

You should be able to see all but members only areas.

You can also contact Michael via RadioMuseum if you are member there.

Cheers

Mike T

VT FUSE · 29th Jun 2014, 3:28 pm

Hello Neil,
a search on this forum would yield the secrets,try searching: Russian Military Subminiature "Pencil Tubes"

All the info there.

Best wishes.

Neil Purling · 29th Jun 2014, 3:29 pm

I have sent an e-mail to Mr Watterson. He may have some interesting insights if I get a response.

28th Jun 2014, 10:12 pm	#1
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,087	1 valve radio with Russian sub-minature valves I wondered how many people have used these Russian 'pencil' valves. There are several types of course, but I bought 1J24B. Has anyone built anything with these ? It could have been an old circuit adapted to using the sub-minature valves. What I have managed to establish is my choice of component is happiest with 45V HT. What's right for the filament supply? I have goodness knows how many NimH AA cells. They seem about 1.2V at full charge. I can't remember what the filament current drain is off-hand, but I can easily wire more AA cells in parallel. I was wondering whether the Electron-Coupled design can be re-designed to use the Russian valve at 45V HT with regeneration by varying the screen voltage. I have done stuff with conventional 6.3V pentodes like the EF39, but nothing with low-voltage valves. The DF9* series can be a bit pricy. I got the ten Russian valves for the same price as one DF91.

28th Jun 2014, 10:19 pm	#2
Cobaltblue Moderator Join Date: Dec 2010 Location: Exeter, Devon and Poole, Dorset UK. Posts: 6,874	Re: 1 valve radio with Russian sub-minature valves Michael Watterson over on VRAT has done a lot with these including replacing D series valves. Just be warned he's very enthusiastic about the Russian Rod Pentodes Cheers Mike T __________________ Invisible airwaves crackle with life or at least they used to Mike T BVWS member. www.cossor.co.uk

28th Jun 2014, 10:45 pm	#3
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,087	Re: 1 valve radio with Russian sub-minature valves Cobaltblue: I don't suppose that the person you named posts here too.......... VRAT won't allow you to even read the threads without registering. There's an interesting link to a circuit on another site, which you can't view for the same reason. I guess I would have a few questions for Mr Watterson.

28th Jun 2014, 11:38 pm	#4
brunel Heptode Join Date: Sep 2005 Location: LEEDS.......North of the River Aire. Posts: 872	Re: 1 valve radio with Russian sub-minature valves They can all be read, without login in. http://www.forum.radios-tv.co.uk/vie...entodes#p87618 Last edited by brunel; 28th Jun 2014 at 11:40 pm. Reason: ADDED EXTRA LINK

29th Jun 2014, 3:28 pm	#6
VT FUSE Hexode Join Date: Aug 2010 Location: Malvern, Worcestershire, UK. Posts: 347	Re: 1 valve radio with Russian sub-minature valves Hello Neil, a search on this forum would yield the secrets,try searching: Russian Military Subminiature "Pencil Tubes" All the info there. Best wishes.

29th Jun 2014, 3:29 pm	#7
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,087	Re: 1 valve radio with Russian sub-minature valves I have sent an e-mail to Mr Watterson. He may have some interesting insights if I get a response.