Telefunken Magnetophon 85 --> EL95 Guitar amp

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Hope this is in the right part of the forum.



What I have is a Magnetophon 85 with a fairly functional amplifier section.
I'd like to turn it into an EL95 guitar amp.

What I basically would like to know is how self contained that amplifier section is. It'd be great if all I had to do was to hook up the power transformer, though I have my doubts that it'll be that easy.

I've not modified a valve based system before but I've replaced capacitors, rectifiers, etc.
 

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Old tape recorders need to used regularly, otherwise their many switches and relay contacts get oxidation and the operation is poor or inadequate. I strongly recommend to clean all contacts and just after that evaluate what it is.

I noticed that after prover service M85 will perform grandly.

EF86's are available easily. Search from net, but check first the contacts of the socket of EF86.
 
It's pitty to destroy Telefunken M85 and according to photos it's in really good shape.

EF86 and capacitors could be found easily and it's not big effort to replace.

A bit problematic could be if you want to find Telefunken's EF86, pretty scarce and expensive!

You can try EF86 / 6267 Siemens, EF86 / 6267 Valvo or EF 86 Philips which are common NOS types and also some cheaper RFT or Tesla EF86.
 
Thanks a lot for the replies.

What are some of the crucial components that usually need to be replaced. All the capacitors ?
what I'm asking is: is there something that with 100% certainty needs to be replaced ?

There's a lot of hum and when I turn down the bass it sounds almost like a tremolo on a guitar amp.
 
Thanks Artosalo,

I cleaned everything as good as I could and it made no difference.

Just checking the capacitors with a meter and I'm getting a lot of very bad values. All the paper ones are off the chart and the electrolytics don't look too good either, so this looks like an almost complete recap. Can a bad capacitor under the EF86 cause microphonics ?

Now I'd be really interested in that schematic Artosalo.
 
Hi,
I recently acquired a pair of amps from 2 magnetophon 85.
I have some questions about the wiring.
There are 3 free cables coming out from the transformer, blue, red, and green. I suppose that is the speaker output. Do you know the connections?
Normally 2 cables are needed. I suppose that probably 2 speakers were connected.
All the other connections are made by a noval plug. Do you know the connections?
I think I find some connections:

Pin 1 unknown
Pin 2 input
Pin 3 not connected
Pin 4 not connected
Pin 5 unknown
Pin6 unknown
Pin 7 Heater
Pin 8 Heater
Pin 9 Ground

So, I miss Pin 1, Pin 5, Pin6.
 
Thanks Artosalo,

I cleaned everything as good as I could and it made no difference.

Just checking the capacitors with a meter and I'm getting a lot of very bad values. All the paper ones are off the chart and the electrolytics don't look too good either, so this looks like an almost complete recap. Can a bad capacitor under the EF86 cause microphonics ?

Now I'd be really interested in that schematic Artosalo.

Is the schematic still available?
 
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