Cany anyone supply any info. about this amplifier?

[OXAUDIO]

All I konow about it is that it was made in France sometime in the 1950s. I am told it was for use with a Pathe Film projector, but there are no identifying marks, other than the number '01972' stamped on the rear chassis panel, on either the chassis or metal case(The latter is elsewhere at the moment)

Tube lineup is 2 x 6AU6(EF94), 2 x 6AQ5(EL90), 1 x 5Z4 Rectifier, plus a 'Magic Eye' indicator tube type 6AF7. I am in the process of tracing out the circuit, which seems to be fairly conventional for the time, except that one of the 6AQ5s seems to be wired as an oscillator

Inputs, each with it's own gain(volume) control, are provided for Microphone(type??) and Magnetic Pickup. A headphone socket(marked 'Casque'), and 3-way function switch, which in one position disconnects the speaker,(substituting a 3 ohm 'dummy load') are fitted

The amp runs from 110vac, the 'live' side of which is routed thru a shorting link in the Loudspeaker Socket, so that power cannot be applied without aspeaker being plugged in

Any help inpositively identifying the make, model, and, if possible, year of manufacture, would be appreciated, as would a circuit diagram, or any technical info.

[Yvesm]

Try here:

http://www.tsf-radio.org/forum/forum.php

Some of thoose french guys (like myself) can understand few english words !

And a larger pix may help.

Yves.

[OXAUDIO]

Thanks for that link, Yves. I will go there and see what I can find. I posed the same question on another forum, and, to date, despite 129 people viewing it, no-one has been able to help.
AS to the picture, I can probably enlarge it, or add a different one, if need be.

[OXAUDIO]

If it helps someone to identify, and perhaps provide some additional info. about the tube amp in my previous posts, I have now traced out the circuit(e & oe!!), which appears to be conventional, except that V3 is seemingly connected as an oscillator, though for what reason I know not. So far as I know the amplifier was made for use with a (?Pathe?) Home Movie Projector

[Wavebourn]

It is from a vintage French tape recorder.

[OXAUDIO]

Anatoly, you don't happen to know what make of French Tape Recorder, this amp. is from, do you. I ask the question because I would like to find an 'official' schematic, plus service info if possible. The Gent. who owns, and asked me to repair. it, told me it was from a movie projector, and a member of the Vintage Radio Discussion Forum here in the UK said that the Oscillator circuit around V3 was used to drive the exciter lamp for the magnetic sound track. Of course that could also be the bias/erase osc. for a tape recorder, hence the 'magic eye' indicator tube. Someone has added a modern gold plated RCA socket(J3), and fitted a 3pin microphone-type socket as a mains connector.(!!)

[Wavebourn]

My conclusion about a tape recorder was made because of mixing of signals from the output tube and from the oscillator. It is obvious.

[Tom Bavis]

There were 16 MM projectors that could play AND RECORD on mag stripe film. Portable cameras generally didn't do sound recording... There's a photo and schematic of such a Kodak amp on my web page: http://www.audiophool.cjb.net/MadeInRoch.html

But a 6V6 oscillator was generally used to drive a 4V lamp with a photocell pickup. Or a DC lamp was used - in either case to avoid hum in the recovered audio.

[kevinkr]

Hi Tom
Your made in Rochester website is pretty cool.. Once upon a long time ago (about 1989) I owned a very pristine example of the ASP-422 which was surprisingly good sounding with the original 6DY7 output tubes in it. Gave up on it and sold it to a collector when I could not get replacement output tubes for it a couple of years later. (Pre Internet and eBay, I could probably source tubes for it today, but almost impossible at that time.)

[JAN Amps]

I think it is more than likely that your amp is from a projector. I own several U.S. Military 16MM projectors with tube amplifiers that were manufactured during the 1950's. They also use a 6AQ5 tube in an ocsillator circuit to drive the 6v exciter lamp for the optical (not magnetic) sound circuit.

Gary