Minimalist Superhet Radio.

[Davek0974]

Yes it does

It was a two-stage circuit but was advised to only build the single stage version to start with to ensure I stayed inside the pantry

[Davek0974]

Thanks, yes I did get an email but I have a problem with very poor short-term memory and I could not remember where I asked the questions in the email, my apologies.

I have only built half the circuit so it's easy to add the last stage, can you suggest a range of suitable valves, I know I don't have a 6L6M in the box. Any common ones work in that spot?

[crackle]

I learnt a lot whilst completing my little project "Minimalist Radio" last year.
Particularly the importance of layout.

Mike

[Davek0974]

Hi.
The transmitter works with just about anything from a EF80 to 6V6 or even an 807. Its a real junk box project. Im going to do another with an EH90 & EF91.

Moving to a new thread, apologies for the hijack

[Cathovisor]

How about a minimalistic FM radio project?
Two Acorn valves and a super regen circuit springs to mind!

Schaub Pirol 55GW comes to mind here: two valves only, a UCC85 and a UEL71 - the UEL71 acting as slope detector and output.

[sideband]

Now that would be an interesting circuit! Any chance of posting it here?

[Terrykc]

The UEL71 is unusual - even the number is wrong! - a signal tetrode and output pentode in one bottle on a Loctal base which should really be numbered in the 20 - 29 range!

[Till Eulenspiegel]

From the Radiomuseum: http://www.radiomuseum.org/r/schaub_pirol_56gwu.html
The UEL71:
http://www.radiomuseum.org/tubes/tube_uel71.html

I can't see how this set was ever any good.


Till Eulenspiegel.

[Till Eulenspiegel]

From the Radiomuseum. A very unusual radio receiver circuit employing two valves.

http://www.radiomuseum.org/forum/arel_51u_51_u.html

Text ist auf deutsch.

Till Eulenspiegel.

[Cathovisor]

From the Radiomuseum: http://www.radiomuseum.org/r/schaub_pirol_56gwu.html
The UEL71:
http://www.radiomuseum.org/tubes/tube_uel71.html

I can't see how this set was ever any good.


Till Eulenspiegel.

I have one, and you couldn't be more wrong about it.

It is actually very good! The sound quality is excellent due to the NFB around the audio stage, and it is far more sensitive than you could ever possibly imagine.

There were other sets in a similar vein: the Grundig 840W being one.
http://www.radiomuseum.org/r/grundig_840w.html

[Cathovisor]

The UEL71 is unusual - even the number is wrong! - a signal tetrode and output pentode in one bottle on a Loctal base which should really be numbered in the 20 - 29 range!

See also EM71, UM4 and ECL113!

The UEL71 has precedent in the VEL11. Then of course, we had the PFL200!

[Cathovisor]

The Twin Acorn FM receiver is a PW design, I've the copy somewhere.
I built it with one valve (super-regen stage) and it worked well enough. With the RF amp it would work very well and stop the interference that these super-regens produce.

When the Germans were effectively forced into FM in 1950, a lot of very innovative FM receiver designs came out and a lot of sets were made convertible as well. SABA made a number of add-ons for their sets, from stand-alones (UKW-Z) to an elaborate one designed to be built in which used a nonode - the EQ80 (UKW-S). Not knowing what the frequency allocation would be, some convertible sets are simply numbered 0 - 100 on the FM scale, others 85 - 100MHz. I have a Nordmende set (Super 198 WU) given to me by the late and much-respected Konrad Birkner that has a super-regen FM adapter in it using an ECF12, a valve specially designed for FM reception. As he said, "don't connect it straight to an aerial!"