Help with a Telefunken Magnetophone 201TS

[Buntudor]

Hi all - thank you for a great source of info.

I am looking for help with a Telefunken Magnetophone 201TS

The reels turn, but there is no sound whatsoever. No hum, no signal at the level meter even when the selector switches and on / off switches are toggled.

I have given the switches a good clean and worked them on and off to free any bad contacts. The mechanical switches move freely and smoothly when playback and record are actioned.

The tape is directly touching heads. There is absolutely no voltage at the internal speaker during playback.

The machine has a 2 core coaxial type wire coming from the selector switch - the other end is not connected to anything and was protruding from the back where the mains cable is stored.

If anyone could let me know why I am getting no signal whatsoever from the speaker / headphone dins or the internal speaker I would be very very grateful. I have a multimeter and can take measurements under instruction.

I have included photos of the strange wandering wire - and a photo of the din sockets that look like they may have been modified in some way?

The 2 green disconnected wires in the photos are for the bulb which I am replacing (it blew today) after 3 weeks of trying to get a sound out of the machine. Also the seat for one of the reels is missing in the photo and having a tiny repair.

Thank you very much for any help.

[DMcMahon]

Hello,

I fairly recently purchased a 201TS but have not yet checked it out.

Are you happy that the tape (s) you are trying to play have recordings on them ?

Make sure that the loudspeaker cut off switch on the rear panel is correctly set, looking from the rear it is the slide switch on the left hand side and should be in the up position.

I am fairly sure like my 204TS that the 201TS VU meter will only monitor the record signal, i.e. no VU meter signal on playback.

Have you checked the main DC supply voltage, according to the schematic it is -13 volts, it should be around -12.5 volts at the negative side of electrolytic capacitor C124 (1,000uF). Probably OK because the bulb is lighting.

The co-axial cable looks a mystery, possibly a mod/add on to connect an input/output ?

David

[Restoration73]

There won't be a dc voltage across the speaker. Most likely cause of no DC is failure of
fuse Si3 (T 800mA) so check that.
As the four track head could replay a stereo tape perhaps the extra cable is for an
external preamp for the other stereo channel.
Circuit and description feature on pages 500-502 of the 1968-69 volume of "Radio & TV
Servicing" book.

[DMcMahon]

Originally Posted by DMcMahon

Make sure that the loudspeaker cut off switch on the rear panel is correctly set, looking from the rear it is the slide switch on the left hand side and should be in the up position.

David

"looking from the rear" should have read "looking from the left hand side panel".

[Buntudor]

Thankyou very very much Restoration73 and DMcMahon.

I got around to looking again today after a delay.

I have tried many differing reels - bought with definate recordings on them and I am 100% confident the switches are in the correct position.
A fuse was blown - and now all 4 correct.

There are 6 fuses sockets in total - but only 4 have fuses in them as when I bought the machine. . The 2 fuse holders that are empty are for 60hz and .8amp.

There is still no sound from the machine. When I place a NCVT anywhere on the amplifier board there is nothing whatsoever.

Also - When I place a NCVT over the fuses, only on appears to be passing voltage - one of the 50hz .315a

I apologise for the lack of knowledge with a NCVT and not being able to name the fuse's Si number.

I have taken a photo of the fuse that succesfully makes the NCVT flash and beep.

I thought I might mention these findings before starting to take voltage measurment (as of the service manual) - just in case it is a fuse problem or a failed transformer.

Thank you again for your very kind attention.
Tyrone

Oh and I replaced the fuse like for like and the bulb lights up.

[Buntudor]

Another update. Sorry if this is a faux pas, but im new to forums.

I have measured the voltage at C124 and it is -12.5v as you said DMcMahon
After testing all the other voltage points from the schematic (thanks Restoration73) there is no voltage on any of them.

What does this indicate?

Thankyou

[DMcMahon]

Thank you for the updates Tyrone.

I had to Google NCVT (Non Contact Voltage Tester), I have never used or seen one of these. One I looked at on YouTube only had an operating spec down to 12 volts, so possibly your apparent lack of voltage may be just that the NCVT will not detect most of your circuit DC voltages. I would use a volt meter to check what actual voltage you have at the various points.

If you were using a volt meter where you confirmed -12.5V at C104 but nothing else elsewhere then that seems unlikely ?

Looking at the schematic the fusing arrangement is not 100% clear to me, I will have to have a look inside my 201.

David

PS. Looking at some more NCVTs they all appear to be for AC voltage only.

[DMcMahon]

A quick look at mine and the fuse situation is clearer. Mine only has 3 fuses because it is 50Hz only.

So yours with 6 fuses (holders) must be a 50/60Hz model, your model is probably designated 201TS E 50/60. So yes you should have 4 fuses (2 x 315mA/0.315A & 2 x 800mA/0.8A (0.8A in the 50Hz positions). All these 4 fuses should be live (AC voltage).

[Buntudor]

Thank you DMcMahon
You are correct on all points of your last message.
I measured the test points with a multimeter and there is 0 volts on everything except the negative of the 2500uf capacitor:

* Correction * the negative of the 2500uf capacitor is -13.9v * and not -12.5 as I posted earlier. Apologies for the error.

I replaced this capacitor and the fault still remains.

Please can you tell me how to check that the fuses are passing current?

[unitelex]

I think most would test continuity (low resistance) across a fuse with the power removed from the set.
Alternatively with the set powered, carefully use the meter on the DC volts setting to test the voltage on each side of the fuse in turn (black probe remaining on the chassis metalwork), red probe touching each side of the fuse in turn. If the fuse is blown the voltage would not be the same on both sides of the fuse.

Best to also try probing on the metal contacts of the fuse holder, sometimes the fuse holder is not making contact with the fuse due to oxidation etc.

[DMcMahon]

It sounds very strange if voltage present at C104 but nowhere else, what about the main capacitor C128 (2,500uF) ?

What test points are you referring to, or do you mean just other parts of the circuit ?

If you actually do have -13.9V across C104 then that would suggest all the fuses are good but still double check the continuity of the fuses to be sure. Note there is 240 volts AC mains voltage across the two 0.315A fuses, be careful and safe if doing any live monitoring.

Did you check out the loudspeaker cut out switch ?

David