Hi Guys,
This one might be a challenge. Kevin Chant has a heading for Aristone on his site, but no material.

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I know it's a radiogram, and can identify one valve 6BE6.
One valve is missing, and the rest are unreadable,
BUT I have a 6V4 rectifier here, and the valve right next to
the missing one ends in a 4, and looks exactly the same as a 6V4 to me.
I assume the audio amp valve is the one missing,
and it was the audio amp that was closest to the output transformer.

Any info would be appreciated.

Its got 9 pins, that narrows the field. Most likely 6M5

Compare the pin outs with it?

Marc

I would have guessed 6M5 since I've seen a few other
portables and some Krieslers use the same.
It still would help to ID it and get a schematic because I don't
know the rest of the valve set without one,
and it would also verify 7000 Ohm output transformer.
One wax capacitor is also busted so badly that I can only
guess it's value based on the size of similar caps.

The only four valve radiogram I can find that uses a 6BE6, 6M5 and 6V4 is a Precedent 415. The fourth valve is a 6N8 used as both an IF amp for radio and AF amp for records.

This is a five valve set though, it's just that one is missing.
That's the one I think is 6M5.

Whoops.. Scraps, if you looked at the picture and counted valves,
you probably missed the one obstructed by the power cord!

I brought this one back tonight woohoo!
Both transformers are good, the rectifier was in the socket where
the output valve should have been,
and the socket that should have had a rectifier in it was vacant.

Now my only dilemma is not knowing what the speaker impedance should be.
The owner says the cabinet had a modern 8 Ohm speaker in it which doesn't sound right.
I tested with a 4 ohm and 8 ohm in series.

6M5 should want to see a 7k primary I think, but that still
leaves all sorts of options for the secondary.

See post 3 from GTC in this thread;

http://vintage-radio.com.au/default.asp?f=2&th=226#1526.

Because the secondary reflects the impedance, the speaker and secondary needs to match to reflect the 7k in the primary. Even if you use the correct transformer with the wrong impedance speaker the load on the output valve will be wrong.

If you measure your transformer you'll be able to figure out the correct impedance speaker. Note that speaker impedance is about 1.25 times the DC resistance or thereabouts.

I don't have a variable power source but just use a plug pack which is about 13.4 volts to measure the turns ratio which works well but complicates the math slightly.

Thanks