Hi All,
Does anyone have a circuit diagram for an HG Palmer RM1R radio?

Thanks in advance.

That could be interesting as it is likely "Badge" engineered. I.e. Any body could have made it: Like I have a 1935 Chrysler / Dodge car radio fixing it.

It was built by Astor, however, deep down its an American Philco. Similar with Holden, where some of their stuff was NASCO Airchief; Airchief was Firestone Tire & Rubber. But made here by Astor.

May need some photos of the internals

Is it a transistor or a valve radio?

KG Harris made both for HG Palmer. The other possibility is Stromberg Carlson.

That should narrow it down.

Radio is a 3 valve set.

What valves does it have?

KGH had "Calstan" as their own brand.

So is it a Calstan 302? That is their only 3 valve radio.

https://www.kevinchant.com/uploads/7/1/0/8/7108231/302_1.tif

Vavles in radio are:
6N8; 6AN7 & 6GW8.
Rectifier is solid state.
Sorry Ian, it's not a Calstan 302.
I'll upload some photos over the weekend.

6GW8, eh?

That puts it right at the death knock of HG Palmer and rules out Stromberg Carlson. So it's a KGH, anyway.

Brad, those hospital radios were by KGH, weren't they? Might be the same beast.

Interesting valve combination, makes it the equivalent of a normal 5-valve radio.

I'd guess that your radio was made in the 1960's, not long before the company collapsed.

Interesting: This site is the only one that keeps sporadically locking up, or refuses to load. So this is a second attempt, a few hours later.

There are similarities to a Music Master A534G, in concept.

6GW8 is a 1961 tube.

This should be easy to reverse engineer. 6AN7 ( Triode Hexode) will be the frequency changer /oscillator; 6N8 (Hi mu RF Pentode Duo diode) IF amplifier & demodulator (diodes) possibly AGC; 6GW8 (Triode / Pentode) 1st Audio & Power amp. The Pentode part is likely the same or very close to 6M5 as it was used even in TV tubes and I suspect other tubes, like the video amp 6CK6. difference, pin6 Grid 3 Internally connected on 6M5

It may have Polyester rather than paper caps, If its got ELNA caps, they may test OK otherwise replace all electrolytic caps 500V for B+.

Photos before you touch anything are desirable.

Marc

Photos uploaded.

G'day Ian,

The boxy radios I have mentioned previously that were used at Gladesville Hospital were indeed Calstans Some were valved and others solid state but the cabinets were very similar. Just four sides of plywood with veneer with a 60's-ish grille cloth and a cheap plastic tuning dial and a couple of control knobs.

I've always had trouble getting photos of them but just found one on WAI2SE's site. First photo here. That is the solid state version. The valve version is a tad taller.

UPDATE: I just found a photo of the valved version on Paul Ledger's site, here.

There were a couple of these radios on each ward, usually one in the charge nurse's office and another in the common room where the patients spent time. These rooms had a radio, television, the usual furniture and newspapers and magazines, etc.

Well it doesn't look like it's one of these.

It's not a Precedent, they wound their own IFTs, those ones are Philips.

Ferguson transformers. I'm thinking KGH. Maybe it's got a KGH number that starts with 4, it's not a 302 that's for sure.

It looks a bit like an EKCO but their Oz mantle radio was lots neater.

There's enough info in those pics to draw a circuit if you think you need it.

Looks like a pretty simple radio. Just replace those 5 wax caps, check the speaker transformer, and it should be good to go.

I've already started to draw a circuit diagram, though I'm sure there will be some component values that can't be determined.

A case in point is the resistor visible in the last photo.

Under a very bright light, it appears this is red, black, brown: 200 Ohm, however, resistor measures in the vicinity of 4K, so I am suspecting it's "slightly" high in value.

Paper caps & electros have been replaced & surprisingly enough, radio works.

Hopefully someone will recognise what it is.