seeking advise

Looking for an expert opinion/advise.

 

Part of my collection of audio equipment is a 1964 NORDMENDE Samba C Stereo Console. Built-in is a DUAL 1007A changer with a CDS620 ceramic cartridge.

I don't operate the unit very often, but lately the output when playing LP's is very much reduced and rather flat (not so radio receiver operation).

The problem started slowly, cutting in and out of normal with some crackling, until the now present condition.

 

I suspected the ECC808 tube and replaced it, but it made no difference.

That leaves the cartridge, or perhaps one of the components on the circuit board.

 

Any suggestion, anyone?

 

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Hi Rolf,

just a preface: Please ask questions starting from the model page. Then one could open schematics directly, and in case of success the thread could later be found there.

As the ECC 808 does the audio job for radio reception as well, it is unlikely that it is the culprit. If at all, it could be the TA/PU switch contacts, but I think you'd have noticed that when operating it.

Here's a list of the more likely bugs:

- Newer crimped DIN cables. Sometimes the resistance increases. This may cause the flatness you noticed. Good: Easy to measure. Nasty: Can disappear, when you move the cable. Difficult to diagnose then. 
- The muting contacts (if present) of the turntable may require cleaning. 
- If the cartrige has a quick release like the Dual 1019, check its contacts. 
- A litz wire causing a short in a connector. Nasty, if you don't suspect it, because through resistance is not affected. 
- If all that doesn't help, route the cartridge directly or after the suspected point to directly to the set (or another receiver) to check it.

If both channels are affected to the same extent, check the ground return path.

Regards,

Steffen
 

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The Dual cartridge CDS620 is not a ceramic but a crystal reproducer made from Seignette salt. These reproducers are prone to get damaged by moisture after a longer time.

This could be the reason for the described behaviour.

(Btw, your post has been moved to the model page)

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Hello Steffen, 

Thank you very much for your reply and suggestions.

As the saying goes, better late than never. I finally got around to follow up on your suggestions.

Lucky I started with the small set of contacts at the changers mechanism (don't know what to call them). They appeared dirty, so I applied some contact cleaner and that was the fix.

All's working well again.

Best Regards,

Rolf

 

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