Help restoring Telefunken Rhythmus Hifi

[nickfox]

Hi everyone

I'm new to the forum. I have a Telefunken Rhythmus Hifi that I'm trying to restore. It seems to have all original parts and tubes. And it actually works, mostly. I'm able to get things on the radio. The only thing that is not working is the turntable. It doesn't spin.

I'm comfortable working around (guitar) tube amps and know what precautions to take. This is my first radio. I'd like to try to get the turntable working and also I want to replace any caps that might need replacing. I don't want to replace all the caps, just the ones that need it. I also would happy to replace anything else you suggest. I've attached a couple of pics.

thanks
Nick

[Audio1950]

Hi, and welcome to the forum.

So that we can help with the turntable problem, can you please post a picture of the record deck?

Barry

[Herald1360]

Only 4 push buttons and no magic eye make it difficult to identify on Radiomuseum. Any more details on which version of Rhythmus it is?

A valve lineup might help with ID too.

A picture of the deck would help with model specific suggestions but the usual advice to dismantle, clean off any old hardened grease and relubricate (ONLY where lubricant was used before!) will apply.

Capacitor wise, replace any paper dielectric types at any place in the circuit where slight parallel leakage resistance (10M or less) would upset dc levels. Typically output valve grid coupler, screen decoupler, AGC decoupler and any capacitor where a short circuit failure could damage other components!

[ms660]

No schematic in the link but it shows the record deck:

https://www.doctsf.com/telefunken-rh...-fr/f30836/o=y

Lawrence.

[nickfox]

Wow, that was fast. I've written what each tube is and placement on the piece of paper. I also included the writing on the two transformers. Also on the paper in the bottom left corner, there is a little metal thing that looks it goes on a shaft somewhere. That was floating around in the bottom of the radio. I'm hoping that might have something to do with the turntable not spinning...

n

[roffe]

The Telefunken Musikus 108Z looks close enough.

https://www.radiomuseum.org/r/telefu...108z108_z.html

[Station X]

Can you hear the turntable motor running? If not there's either no power to the motor or it's seized up.

If you remove the circlip from the turntable shaft you'll be able to lift of the turntable giving visibility of the motor and drive arrangements.

[Edward Huggins]

The top right valve will most likely be an EL84. To start the player, try pulling the tone-arm to the right. That collar with a grub-screw through might well belong to the deck?

[nickfox]

Ok, I took the deck off and I was able to see that the motor is running when I pulled the tone-arm back.

Also, I found another valve (in the picture) that is an ECC85. It was hiding the first time I looked.

I've been reading your article "Reviving your old Record Player" and I just learned that deck means turntable. I'm American, I kind of thought it was but wasn't 100% sure...

n

[Station X]

Does this mean that the turntable now rotates?

The ECC85 will part of the circuit designed to receive VHF/FM signals.

http://www.r-type.org/exhib/aaa0241.htm

[nickfox]

Originally Posted by Station X

Does this mean that the turntable now rotates?

Yes, the turntable is now spinning but it needed a little bit of help. If you look in the image, there is an arm (with the red arrow) holding the black rubber disk that was not pressing against the motor spindle. When I pushed it with my finger towards the spindle, then it engaged and started working.

I tried to change the speed from 16 to 33 and it wouldn't change until I pressed down on the shaft (holding the black disk) and then it was hitting the proper place on the motor spindle.

You can clearly see the rust on that shaft. I think that may be the biggest problem. I have some very fine sandpaper (up to 2000 grit) and some 3 in 1 light oil. Should I try to remove that shaft and clean it up?

n

[Edward Huggins]

Clean the centre shaft (spindle) in situ. No need to remove. For the player to work, the black disc (idler wheel) has to simultaeneously press against the motor drive spindle and the inner rim of the platter. It can only do this with platter in place i.e. the motor spindle turns the idler, the idler turns the platter.

[Audio1950]

I wouldn't use 3 in 1, that turns sticky after a while, and will make more problems. Use sewing machine or hair clipper oil.

[nickfox]

Originally Posted by Edward Huggins

Clean the centre shaft (spindle) in situ. No need to remove. For the player to work, the black disc (idler wheel) has to simultaeneously press against the motor drive spindle and the inner rim of the platter. It can only do this with platter in place i.e. the motor spindle turns the idler, the idler turns the platter.

Good, I was worried about having to take things apart and having a spring shoot off into oblivion. There is a spring on the turntable and I was putting the turntable back onto the spindle and I heard it drop into the radio. Luckily I found it quickly. I hate when that happens...

Originally Posted by Audio1950

I wouldn't use 3 in 1, that turns sticky after a while, and will make more problems. Use sewing machine or hair clipper oil.

Ok, that's very good to know. I will not use the 3 in 1. I sent out a couple of emails trying to find sewing machine oil. I may need to wait until tomorrow and try and find it in town somewhere. I live in a pretty remote area.

Will this ptfe grease work, or should I just be patient and wait to find the sewing machine oil?

n

[nickfox]

I'm seeing another problem. Everything seems to be engaging properly with the turntable off. But when I put the turntable back on, the idler wheel doesn't seem to have enough friction or isn't close enough to the turntable to make it spin.

The idler wheel looks to be in good condition but it is very hard like old rubber gets.

n

[nickfox]

Please excuse all the fast and furious posts. I cleaned up everything with isopropyl alcohol and tried again. I stuck my finger underneath and pushed on the idler wheel shaft and something seemed to make a clicking noise and it started working.

I've turned it off and on several times now and it's been running for about 30 minutes. I measured three times now and it's seems to be running at 35 rpm. Is there a way to adjust that?

n

[Edward Huggins]

No, that kind of speed variation is to be expected on a deck of this age and given it's fairly basic specification. It may have been like that from new.

[nickfox]

Thanks Edward, I've got the idler wheel arm/shaft cleaned up and put a drop of sewing machine oil on it. I will finish testing the turntable as soon as my Steely Dan Aja album arrives.

Originally Posted by Herald1360

Only 4 push buttons and no magic eye make it difficult to identify on Radiomuseum. Any more details on which version of Rhythmus it is?

Capacitor wise, replace any paper dielectric types at any place in the circuit where slight parallel leakage resistance (10M or less) would upset dc levels. Typically output valve grid coupler, screen decoupler, AGC decoupler and any capacitor where a short circuit failure could damage other components!

Chris, I actually found a magic eye tube in this radio. It's painted gold and is a philips EM34. If you look at my first post, you can see it just to the right of the volume knob.

To further help with identification, I've attached an image of the back cover. I also found a number stamped on the back of the chassis: 036463

In the third image, there is an aluminum can that I *think* is a coil. Do you agree?

I'm now trying to identify capacitors that need replacing. I have an MK-328 tester and a multimeter. So far I've found 3 types of caps.

In the second image, there are some very flat caps that I have never seen before (red arrow), one paper helgo cap (blue arrow) and a bunch of black plastic helgo caps (yellow arrows).

Without a schematic, I can't really identify things. With all the added information, can anyone help me find a schematic?

thanks
n

[G6ONEDave]

The aluminium can in picture 3 looks more like an electrolytic capacitor than a coil to me. A pic of the underside would confirm it.

[nickfox]

Originally Posted by G6ONEDave

The aluminium can in picture 3 looks more like an electrolytic capacitor than a coil to me. A pic of the underside would confirm it.

I thought it was a cap at first also, but when I put my esr meter across it, it was showing up as a coil. But I didn't take it out of the circuit so it may have been confused (like me).

n