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 Identifying a barn find kit radio
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 Return to top of page · Post #: 1 · Written at 12:35:15 PM on 6 July 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1895

This little home-made mantle radio might be a Little General (late 40's components, EFCO dial) but the circuit seems a bit too low rent.

ECH33 mix/osc, cathode biassed no AGC
RCS coils
A single RCS IF transformer
6J7G anode bend detector
Passive volume control fed from the plate of the 6J7
6V6, cathode bias.
MSP 5" PM speaker
5Y3
Filter choke

This thing probably doesn't need pictures but I will post some when I get a chance.

Sound familiar to anyone?


 
 Return to top of page · Post #: 2 · Written at 2:27:54 PM on 6 July 2020.
Johnny's avatar
 Location: Hobart, TAS
 Member since 31 July 2016
 Member #: 1959
 Postcount: 407

Little or Big Jim.
Radio TV and hobbies?
JJ


 
 Return to top of page · Post #: 3 · Written at 2:57:00 PM on 6 July 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1895

Ah yes, that's right, there was a "Little Jim" series in R&H. I had a good collection of R&H once but it was lost in a flood caused by a blocked stormwater drain.

This particular radio could have been SO much better with a little more design thought. I am very tempted to modify it....

The design of this is reminiscent of a radio R&H did in the early 50s that used (from memory) a 6BE6, 12AX7 and a 6X4. The twin triode was a regenerative detector and output stage. Single IFT with a tickler coil added for the regen. They did a reprise the following month using a 6AB8 / ECL80.


 
 Return to top of page · Post #: 4 · Written at 4:32:13 PM on 6 July 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4330

Visitors arriving but somewhere in an A4 file, I should have circuits for most "Little Jim's" & others


 
 Return to top of page · Post #: 5 · Written at 8:00:21 PM on 6 July 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1895

Yes Marc that would be appreciated.

If it is an actual Little Jim then I'd be more likely to leave it as it is (and try to find out what the reasoning for such a dull design was....)


 
 Return to top of page · Post #: 6 · Written at 3:19:35 PM on 7 July 2020.
Gandhn's Gravatar
 Location: Windella, NSW
 Member since 5 November 2010
 Member #: 770
 Postcount: 343

I have just spent a pleasant couple of hours searching through the RTV&H index and the CD of all issues, looking at all Little Jim and Little General radios and did not see anything resembling the components in Ian's post.

Little Jims were all battery sets and just 1 or 2 valves, some with reaction.

Little Generals were all standard superhets, using 2 X IF transformers, and none of the valves mentioned except 6V6.

Harold


 
 Return to top of page · Post #: 7 · Written at 7:49:24 PM on 7 July 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 1895

Thanks VERY much Harold. I don't recall seeing such a dumb (should I say "deaf") design. I'm happy it;s been confirmed.

Looks like it would have the sensitivity of a crystal set and a THD figure approaching 50% on modern AM transmitters. I won't feel bad about improving it.


 
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