Home Made TRF - Page 3 - UK Vintage Radio Repair and Restoration Discussion Forum

MALC SCOTT · 27th Apr 2008, 7:53 pm

Quote:

Originally Posted by Neil Purling

I think heatercathodeshort presented this design to the forum in post 23 of this thread:
https://www.vintage-radio.net/forum/...home+built+TRF

When i try to access this page, a message states that i do not have permission to do so

HMV 1120 · 27th Apr 2008, 7:56 pm

Snap?

paulsherwin · 27th Apr 2008, 8:16 pm

It had been deleted from the public forum. I have reinstated it.

Paul

MALC SCOTT · 27th Apr 2008, 8:47 pm

Cheers Paul

Neil Purling · 28th Apr 2008, 8:35 pm

I gutted and rebuilt my radio. I use a 'weaker' RF pentode like a EF36 that gives smoother reaction control. The AF o/p is still a 6V6 but I drive it with the triode stage of a EBC33 or 6Q7. The gain of the EBC33 is around 30 & the 6Q7 is given as 70. This gives more volume than you need in a radio. If you go for full volume there is some instability: It is the volume rhythmically (apparently) going up and down. Perhaps I need more de-coupling adding into the supply to g2 of the EF36?
Anyway I don't think my speaker is that brilliant. It is a mottled brown bakelite case by Raymond with a mystery driver, that could be by either Rola or Celestion as there is a CT** number stamped on it. They also used a Magnavox unit.

27th Apr 2008, 7:56 pm	#42
HMV 1120 Hexode Join Date: Jan 2007 Location: Weeting, Norfolk. Posts: 465	Re: Home Made TRF Snap? __________________ Real radios glow in the dark M6GLD

27th Apr 2008, 8:16 pm	#43
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,966	Re: Home Made TRF It had been deleted from the public forum. I have reinstated it. Paul

27th Apr 2008, 8:47 pm	#44
MALC SCOTT Octode Join Date: Aug 2006 Location: Willington, County Durham, UK. Posts: 1,499	Re: Home Made TRF Cheers Paul __________________ Malc Scott

28th Apr 2008, 8:35 pm	#45
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,087	Re: Home Made TRF I gutted and rebuilt my radio. I use a 'weaker' RF pentode like a EF36 that gives smoother reaction control. The AF o/p is still a 6V6 but I drive it with the triode stage of a EBC33 or 6Q7. The gain of the EBC33 is around 30 & the 6Q7 is given as 70. This gives more volume than you need in a radio. If you go for full volume there is some instability: It is the volume rhythmically (apparently) going up and down. Perhaps I need more de-coupling adding into the supply to g2 of the EF36? Anyway I don't think my speaker is that brilliant. It is a mottled brown bakelite case by Raymond with a mystery driver, that could be by either Rola or Celestion as there is a CT** number stamped on it. They also used a Magnavox unit.