rees-mace: 5 tube

I have a 4-tube suitcase portable Rees-Mace "Gnome" which appears to have a similar circuit to the "5-tube" Rees Mace schematics shown here. 

It features a built-in cone speaker and loop antenna in the hinged lid.

The first tube is a screen-grid RF amplifier (Mullard PM12M) followed by a triode grid-leak detector and two triode audio amplifier stages (PM2HL & 210HL, if I recall correctly).  All are 2 Volt British "accumulator" types.

As found, it had three Burgess 45 Volt "B" batteries dated 1934 and an unmarked "C" battery with several unusual female "banana" plug sockets so the bias voltage(s) could be selected.  The accumulator (storage battery) was not with the set when I found it, so I don't know what it looked like or how it was connected.

It has two bands: long and medium-wave.

The March 1939 issue of "Radio News" magazine shows a curious boy at the beach looking into the guts of one of these sets.

 

Attached is a photo of this set.  I have several more photos which I can upload soon as I figure out how to get this model added to the Rees-Mace list on the museum site.

 

^^;;^^

Attachments:

• ReesMaceGnome (26 KB)
• Reese-Mace Gnome (115 KB)

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My father remembers as a boy taking the radio battery to a Cycle shop on the Lisburn Rd. in Belfast to get it charged. Not sure if during late 1930s or early 1940s. He doesn't remember what make or Model of Radio though.

Are you asking what to use as the Accumulator?

If the heater filaments are in parallel, then it was a single Lead Acid cell, probably in a glass container. Hence 2V filaments. You could probably use a pair of series 10AH D cell NiMH and a suitable series resistor or even a silicon diode to drop about 0.5V (A fully charged accumulator cell could be about 2.3V). Certainly I've seen single Lead Acid cells. but not for many years. Plenty on the Internet..

I think it would have looked a little like these Modern 2V deep discharge cells

Google Cyclon and also 2V Lead acid battery

Likely 10AH is 10 to 15hrs, add up all the filament currents. Maybe it would have been from 10AH to 20AH sized cell, just guessing.

A lovely find :-)

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Dear Douglas,

your Gnome model isn't listed here in RMorg, so please make a new model suggestion for it. Follow the link "Create New Model" from the main page. Pictures can also be loaded along with the new model suggestion.

Regards,
Bernhard

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