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Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players Open-reel tape recorders, cassette recorders, 8-track players etc.

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Old 8th Sep 2020, 1:39 pm   #1
DMcMahon
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Default Telefunken Magnetophone 201 TS

Brought this 2 track, sold state, single speed late 60's R2R fairly recently.

It looks in quite good condition and was sold as fully working.

Had not really looked at it until yesterday while trying to offer some support for the other 201 TS Thread.

It arrived from Germany with its mains voltage selection switch set to 220 so changed it to 240 volts, after first unseizing the switch. Replacement of 2 pin mains connector and 2 core cable by 3 pin/3 core still to do.

Powered it up this morning and it is making a terrible loud noise from the motor area, motor is rotating but not the capstan/flywheel and no operation at all of the tape transport. Not a good start.

Presently struggling to remove the top panel to investigate further as the Selector/Function control knob is refusing to be removed.
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Old 8th Sep 2020, 3:39 pm   #2
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Default Re: Telefunken Magnetophone 201 TS

Pulled off the Function selector knob using a looped ty-wrap, it was really tight, even after a spray/soak of WD40.

Found the motor pulley hanging off the motor shaft, luckily it pushed back on easily and and appears to be a tight fit. Will see how it runs, it may need a spot of glue to secure it more firmly. Horrible noise must have been the spinning motor shaft hitting the underside of the pulley.

Now the tape transport works, motor is quiet now.

Both spool plates have the usual problem (with this type of plate) where some parts of the 3 plastic retaining fingers are broken away, should not cause a problem unless the fingers break off all together.

The little indicator bulb by the VU meter was not lit, found that the bub was screwed in cross threaded so not making contact with the bulb holder bottom contact.

Found 3 small pieces of broken brown plastic inside, one I think off the spool plates, nothing important I think.

Next to try tape playback.
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Last edited by DMcMahon; 8th Sep 2020 at 3:50 pm. Reason: Typo correction
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Old 8th Sep 2020, 8:43 pm   #3
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Default Re: Telefunken Magnetophone 201 TS

Quote:
Originally Posted by DMcMahon View Post
Both spool plates have the usual problem (with this type of plate) where some parts of the 3 plastic retaining fingers are broken away, should not cause a problem unless the fingers break off all together.
Spoke too soon. The broken retainer fingers are causing the spools to jump around with loads of noise in Play, RWD, FWD & braking/stopping. Will see if I can superglue something (like a short strip of ty-wrap) to extend/repair the fingers or maybe just stick the spool retainer plates down temporarily with non permanent fixer/sealant.

Good news is that Playback works quite well, sounds quite good, although the tape I tried was Italian opera, so will need to listen to some music I am more familiar with to judge better. With the volume wound virtually fully up there is noticeable distortion, need to do more checks to see if due to the recording on the tape, the amplifier or speaker etc.
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Old 10th Sep 2020, 5:35 am   #4
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Default Re: Telefunken Magnetophone 201 TS

Are those retainer fingers intended to snap into the holes in the bottom plates then? The holes in the bottom plates look elongated, with a wider part in the center, which I'm assuming is where the fingers are intended to snap in. Does there seem to be any reason for the elongated holes? It almost looks like the fingers are meant to be entered into the wide part, then the reel table turned so the fingers slide to the end position of the elongated hole, but I've never dived inside one of these so I don't know.

BTW, surely this is a 4 track machine, with the big knob on the lower head cover being the track selector?
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Old 10th Sep 2020, 7:46 pm   #5
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Default Re: Telefunken Magnetophone 201 TS

Yes you are correct Ricard, it is 4 track (1/4 track) for some reason previously I was convinced it was a 2 track machine.

Yes the fingers/prongs fit into the middle of the cut out section, then the spool plate is rotated to lock/slide the fingers into the end position of the elongated hole.

Of course when they lock you cannot actually see at exactly what position the finger is in relation to the elongated holes. I may sometime remove bottom section of the table (to see it from underneath) and fit a plate that does not have broken fingers (another machine) to see exactly where the fingers finish up when locked.

On this machine for the time being I have used some silicon sealant to hold the plates down in position, still to see if this will hold with usage.

David

Last edited by DMcMahon; 10th Sep 2020 at 7:51 pm.
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Old 11th Sep 2020, 5:34 am   #6
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Default Re: Telefunken Magnetophone 201 TS

Thanks for the explanation - I would assume there's some sort of detent or similar at the end of the holes to avoid the fingers just sliding back, although I suppose it's impossible to see without dismantling the lower part with the holes in it, and with the fingers partly snapped off it's impossible to feel if the fingers 'click' into place at the end of their travel.
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Old 11th Sep 2020, 10:30 am   #7
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Default Re: Telefunken Magnetophone 201 TS

I do not think there is a detent as such but not really sure, assume they just mechanically latch in, the fingers are very fragile, poor design. Will definitely have a look at the underside of a good working one to better understand.

David
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Old 12th Sep 2020, 10:49 pm   #8
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Default Re: Telefunken Magnetophone 201 TS

Tried Playback on some more tapes, no sign of previous distortion heard on first tape tried, must have been a bad recording.

Replaced the old mains cable and plug. Cleaned heads and tape path plus other general cleaning. Cleaned switches and pots.

Next to try recording.
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Old 14th Sep 2020, 1:45 pm   #9
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Default Re: Telefunken Magnetophone 201 TS

Quote:
Originally Posted by DMcMahon View Post
I do not think there is a detent as such but not really sure, assume they just mechanically latch in, the fingers are very fragile, poor design. Will definitely have a look at the underside of a good working one to better understand.

David
Stripped down the Supply Reel table from a 204 TS which has intact fingers on its spool plate (Photo # 1).

Photo # 2 shows a finger, the horizontal part is what breaks off, the fingers are not as long or as pointed as I thought they were.

Photo # 3 shows the underside, the fingers will only fit into the centre wider part of the elongated slot and when the plate is rotated (CW or ACW) the fingers rise up a short slope before at the end of the slot dropping into a recessed well. It takes quite a bit of force rotating the plate in the other direction to get the fingers to come out of the well, this is probably where the fingers are likely to break.

Photo # 4 shows a finger in the middle of the slot.

Photo # 5 shows a finger locked in the well.
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Old 14th Sep 2020, 9:31 pm   #10
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Default Re: Telefunken Magnetophone 201 TS

Thanks for posting those pictures. They really show how the latching works.

It looks like the finger is subjected to quite a lot of sideways stress in its resting (end) position which can't be good either.

I agree it does not look like a good design.

I wonder if it was intended as a one-way assembly design, i.e. it was never meant to be separated after initially being put together. Or does one need to separate the pieces in order to dismantle the pulley section (or get the top part off)?
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Old 14th Sep 2020, 9:39 pm   #11
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Default Re: Telefunken Magnetophone 201 TS

If the reel table ever needs to be removed (maybe to service/adjust the clutch), you have to remove an e-clip that secures it the shaft, the circlip is only accessible once you remove the top spool plate.
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Old 25th Sep 2020, 8:34 pm   #12
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Default Re: Telefunken Magnetophone 201 TS

Microphone and line recording (from the Radio/Phono DIN) and subsequent playback checked out very well. Checked out external loudspeaker operation all good.

Also checked the high impedance playback output from the Radio/Phono DIN, to get this to work you have to switch off the internal loudspeaker and wind the volume up towards max.

So overall all main operations work very well. Two minor items to look at sometime, 1. An intermittent mechanical squeak on Playback, not very noticeable when listening to music, 2. With the volume at max there is a slight hum noise (even with Playback paused), not noticeable with music playing.

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Old 25th Sep 2020, 11:34 pm   #13
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Default Re: Telefunken Magnetophone 201 TS

Regarding that playback squeak, it's not just the tape occasionally rubbing against the flange of one of the reels?
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Old 26th Sep 2020, 12:03 am   #14
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Default Re: Telefunken Magnetophone 201 TS

No I did check for that, the tape does get close but no contact.
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Old 1st Oct 2020, 8:32 pm   #15
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Default Re: Telefunken Magnetophone 201 TS

Investigated the playback squeak but the more I checked the more intermittent it became, but was able to conclude that it only occurred when the Take Up spool was heavily loaded with tape.

After a big spring clean of all the top section parts that moved and lubricating where required the squeak has disappeared.
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Old 2nd Oct 2020, 5:09 pm   #16
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Default Re: Telefunken Magnetophone 201 TS

Checked out the slight hum noise on Playback at max volume setting. Found that only obvious when Function Select Switch is switched to position 1 (tracks 1 and 2 I think) or position P (combined/paralleled tracks 1/2 & 3/4), not obvious in position 2 (tracks 3 and 4).

Tried contact cleaner on the Function Select switch and the volume control but no change, also for good measure cleaned the record and play switches.

Scope monitored the 1,000uF output capacitor C131, small mains ripple signal present which doubled in amplitude when volume increased from 8 to 9 (9 being max setting).

No ripple signal at the volume control or at the collector output of T102, the transistor that the volume control feeds into, also no change of the tiny HF/white noise signal present when volume increased to max.

So even though the volume control being set to max results in the hum there is nothing measurable at the volume control/T102 to reflect this.

A minute amount of hum (buried in noise) seen at the collector output of T103, the next transistor following T102.

So most of the hum is seen at transistors T104-T107.

Measuring the -13V DC supply there is what seems a relatively high mains ripple level of around 400mV p-p, made up of 50Hz and 100Hz. Replacing the 2,500uF reservoir capacitor C128 make no difference to the ripple level. Ripple level at first smoothing capacitor C124 (1,000uF) is negligible. Rectifier is an encapsulated 2 diode full wave rectifier so possibly ripple will be higher compared to a bridge rectifier ?

Tried changing a couple of the other electrolytics around the output stage but no change.

Because the hum is only present with volume at max, have decided not to waste any more time on it.
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Old 2nd Oct 2020, 5:21 pm   #17
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Default Re: Telefunken Magnetophone 201 TS

Years ago I picked one of these up off the street, sadly it had been dropped so BER. The spool tables on mine also came apart very easily. If you need any bits off it I could dig it out.

The feel of the thing reminded me of the Philips 4307/4308 or Thorn DC deck.
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Old 2nd Oct 2020, 11:27 pm   #18
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Default Re: Telefunken Magnetophone 201 TS

Thanks for that Ben. The only part that would be of use currently is the top spool plate if yours have intact fingers (ref Posts 2 and 9) but possibly sounds like yours may also have broken fingers.

David
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Old 12th Oct 2020, 3:51 pm   #19
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Default Re: Telefunken Magnetophone 201 TS

Now gone (sold) to a good home.
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Old 24th Oct 2020, 8:18 pm   #20
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Default Re: Telefunken Magnetophone 201 TS

This can be closed now, thank you Mods.

David
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