[van Jensen]

Now that I am sure that I have found the cause, I have taken a closer look at the belt pulley. There are notches on the inside edge (see detailed photo). In my opinion, these have been driven in there so that the outer ring with the felt sits firmly on the bearing.

I therefore decided to push the outer ring slightly backwards, apply 2-3 drops of glue to the outside of the bearing and then pull the pulley forwards so that it is fixed in place.

Then I readjusted the friction again (approx. 95-100g) and since then the device has been running perfectly again! Keep the fingers crossed!

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[van Jensen]

I checked the adjustment work on the clutch/take-up and carried it out where necessary.
– I set the distance between the belt guide and the spool disc to the specified 3.18 mm
– The distance S (on page 42) between the belt pulley (with felt) and the driving disc (default 0.5mm to 1.0mm) to 0.7mm
– Set the tension of the right-hand spool to between 90-95g with the tape control lever activated (at 19m/s) using screw D.

I have now been able to adjust the following behaviour:
Starting the normal forward works tape motion perfectly. After a longer running time (30 min or 45 min), the belt pulley jumps back a little (not as far as in the pictures above) and the friction of the clutch is lost (see pictures below). If I now push the pulley back to its previous position, everything works perfectly again until the same effect occurs again after a similar playing time.

I have taken some photos which show how the distance to the drive pulley has increased (tape control lever in neutral position).

My next step would be to try to fix the pulley somehow (glue? clamp?) so that it can no longer jump back. However, I have no idea whether this would work and whether I would be putting another necessary function ‘out of action’.

Any feedback/help appreciated – Thanks J.

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[van Jensen]

After I cleaned and oiled everything around the clutch again at the weekend, there was no improvement.

I spent hours with try and error and then I pulled and pushed a little on the clutch with the felt cover and suddenly the rear disc on which the drive belt runs gave way and slipped backwards a little (see pictures). On further testing, I noticed that when I pulled the disc back to its original position towards me, it engaged with a small jerk. The clutch can then engage properly and the takeup spool runs properly for a while. After a while, however, the same problem occurs again. Apparently the disc with the felt has slipped back a little and there is a lack of friction so that the spool runs smoothly and evenly.

1. is it normal that the disc with the felt can come loose and slip backwards (is this part of the functionality of the clutch)?
2. if not, what is the best way to fix it?

Thanks for any  help!

J.

• This reply was modified 1 month, 3 weeks ago by van Jensen.

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[van Jensen]

Thanks, that makes life easier 😊

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[van Jensen]

Hi @Madskp,
I had a look at the thread and learned a lot new stuff about the BC1200 – very helpful. I wasn’t aware how to search in archived forums. Unfortunately concerning my issue no news.

I’ll further try to get the take up spool up and running somehow as I really enjoy listening to tapes on this beautiful machine.

• This reply was modified 2 months ago by van Jensen.

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[van Jensen]

Thank you very much for the link!

I‘ll have a look at it.

Best
J.

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[van Jensen]

What I did so far:

I replace the belt for the take-up reel. No improvement.
Then I also replaced the two belts that run from the motor to the flywheel (many thanks for the very good description how to do this to Danish Sound Parts). No improvement after that either.

I tried it without breakarm (below the right turntable) and without the break wire (around the turntable) – no improvment.

The Capstan runs smoothly and at the right speed in play mode as the music runs in the right speed and without problems.

I therefore suspect that there may be something wrong with the clutch – what could be the problem? Or any other thoughts?

Are there still adjustment options on the device? In the Service Manual it says on page 41 that a screw D can be adjust the pressure on the clutch?

Many thanks in advance for any hint – I really want to use the recorder again.

Thanks
J.

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[van Jensen]

Hi Yann, hi all,

I couldn’t get over the fact that the right channel sounded very muffled during playback. So I unscrewed the black cover of the mixer and cleaned the sound heads again with a little more pressure, patience and alcohol than before. It is definitely easier to get to the heads without the cover.

I also cleaned the “silver guides” on the left and right and the rotating pin to the right of the sound head properly. In daylight I could see that a lot of dirt (abrasion?) had settled there.

Then the test aaaand – it helped. Now I have a clear sound on both the left and right channel and a decent stereo sound when I press both buttons (L+R). Alcohol is not the solution but sometimes it helps 😉

Motivated by this, I cleaned the wood of the machine and treated it with linseed oil varnish. Now the last part of my 70s ensemble, which I have collected, repaired and put together over the last three/four  years, is complete. Okay – almost complete – I am still looking for the U70 headphones … If someone knows someone, pls let me know.

As the icing on the cake, the previous owner sent me a short instruction manual for the instrument that he had found. In the attachment you can see the pictures of the individual devices and the instructions.

Best greetings to France from a very happy
Jens

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Good morning Yann,
Thank you very much for your patience and answer. That sheds light on what I know. I checked it with my head phones and it is as you said. If I just press the L button, it’s double mono. If I just press R I have the muffled signal on both channels.

So it seems that the sound head is not working correctly and I have to find a way how to solve it …

Thanks again for your support – really appreciate it!

Best wishes to France

Jens

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[van Jensen]

Hi Yann,

I cleaned the head with the alcohol and it came of some dirt (see picture). Unfortunately the procedure didn´t help in terms of my issue with recording and playing the right channel properly. It still sounds dull.

I am not an expert with reel machines. Why do I have to press the R and L button? I can hear the music on both channels even if  I do not push the two buttons. But may be no Stereo? Do you know?

Best
Jens

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[van Jensen]

Thanks Yann, I’ll try tomorrow and let you know.

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[van Jensen]

Hi YannChris,

and thank you very much for your immediate reply and your very helpful attachments.
I’ll have a look at the manual and I’ll try to get your WAV file somehow on tape to check the channels.

Concerning the heads: I have Isopropyl alcohol 70% – will this do the job?
Which one of the heads is the one for playing – I assume the right silver one (pls see picture)?
Did I understand right – apart from contamination the heads can also break mechanically/electronically?

Again – thanks for your help!!

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P.S. dimensions in mm  😉

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[van Jensen]

Hi MrRoast,

I made myself a wall bracket from a small alloy profile – you can find the dimensions on the photo below.

Best vJ

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