Gas powered wireless/radio set

[M0ALK Richard]

I too was told about a gas powered radio by my physics teacher when I was at school in the sixties. I rather got the impression that they had special valves that used a gas flame to heat them directly rather than by passing an electric current through a filament, thereby doing away with the need for a low voltage accumulator. Then again I may be completely wrong.

[kalee20]

I have never heard of that, although I have considered the possibility of a gas-heated cathode (tubular, sealed at both ends into the envelope, so that a tiny gas burner could be inserted).

I've also considered the possibility of a solar-powered radio, using photovoltaic cells to generate HT, and a lens or mirror arrangement to focus the sun's rays directly on the cathode instead of and LT supply. Or even a blackened target inside the envelope to catch the rays, with a thick copper conductor to transfer the heat to the cathode. But I doubt if I'll get the chance to try any of these out...

[Mark GØOIW]

I have seen a kerosene powered radio for real, sold under the (obvious) brand name, "Lantern Radio". However, this was a modern solid-state device.
This website http://www.pelam.de/product_info.php...roducts_id=530 sells a very similar product.

Whether this has any advantages, environmental or economic, over an ordinary battery radio we can only speculate.

[kalee20]

It looks the same as the one in posts #7 and #13. And the supplier in #7 is the cheapest!

My two have arrived and I unpacked them tonight, and fired one up. It works! And like a real radio it takes a few moments to warm up.

Next step is to determine power output into various load resistances, and if sufficient, I'll be running my 4-valve Vidor from the lanterns.

[kalee20]

Originally Posted by OErjan_S

eagerly watching this space Kalee20

OK, I filled one of my lamps with paraffin, lit up, and here are results!

The lamp is a wick type (not a pressure type like a Tilley). Build quality is a bit crummy, although the all-important generator is well-made with some good-quality extruded heatsinks to dissipate the heat from the 'cold side'.

The radio works, sound quality not brilliant, but it's OK. There's a slight give-away drop in volume at loud passages, indicative of supply voltage sagging in response to a Class B output stage pulling more current.

So, as to power availability! I disconnected the thermoelectric generator, and connected to a load box. With a tall flame, just below the threshold of smoke, after 5 minutes to warm up and reach steady-state conditions, i measured the following:

Load open-circuit (0mA): Vout=3.8V; Pout=0

Load 56Ω (35.7mA): Vout=2.0V; Pout=71.4mW

Load 27Ω (49.2mA): Vout=1.33V; Pout=65.5mW

Load 15Ω (59.3mA): Vout=0.89V; Pout=52.8mW

Load 6.8Ω (70.5mA): Vout=0.48V; Pout=33.9mW

Load 3.3Ω (72.7mA): Vout=0.24V; Pout=17.5mW

I didn't try to find the maximum power as it is certainly less than 3.8V x 35.7mA or 136mW. Two of these would struggle to chuck out a quarter-watt, so no chance of powering my Vidor 4-valve portable. If there was any simple improvement, I would suggest a much larger supply capacitor to act as a reservoir to maintain voltage during music peaks - maybe a 1F supercapacitor?

Now, I have two of these lamps but as I would need 8 or so to run the Vidor, I shan't take this any further! So, if I keep one for myself, is there anyone who would like the other, either collect for £15 (less than I paid) or posted for £21?

[Framer Dave]

I'll take it please. PM sent.

Regards,

[kalee20]

This photo (a link from the Iranian collection thread) shows a magnificent thermoelectric generator. No data - but I still want one! Makes the recent acquisition (as above) pale into insignificance!

[switcher]

Interesting thread, any chance of a pic of your set-up, please, kalee?

[george.teacher]

Hi folks,

These radios were developed in the USSR. They were useful in areas without electricity.
Here is a link :
http://oldradio.onego.ru/ARTICLES/RADIO/tgk_real_l.htm
for a radio of the 50s.
I know that it was still produced in the 60s but I can't find any picture of the later models.
I had seen one when I was a kid.
Bye,
George.