grundig: TK64 (TK 64); open coil on record/playback head

I am repairing a TK64 stereo tape recorder for someone, and it appears that the coil is open for one channel of the record/playback head.  The owner of this recorder owns a second complete unit for parts; however, it appears to me that the coils for both channels of the head are open on the parts unit.

Is this type of failure common for tape heads on these machines?  I'm wondering if it is worthwhile to try to find another unit to get a good tape head from, or if this kind of failure is so common that it is difficult to find a good one?

Are replacement heads available anywhere?

Thanks,

Tom

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Hello Tom,

You could try this company. - the Magnetic Head Company.  They have been helpful  in the past.

Regards,

Roy

I leave as a question fo replies to this thread.

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Hi Roy,

Thank you very much for the link.  I don't often repair tape recorders and was not aware of this company.  The information on the link looks quite promising.  I'll contact them and see what they may have.

Best regards,

Tom

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I checked the information at the website of the Magnetic Head Company, and it appears they have a wide selection of replacement Nortronics heads for tape recorders from a variety of companies.  However, they don't list heads for any of the German companies that produced tape recorders.  They also did not respond to an email question as to whether they could supply a head or know of another supplier for a head for a Grundig TK64.

Does anyone know of a source for a replacement head for a Grundig?

I imagine it could be possible to retrofit an American tape head into a Grundig machine (I can probably find one with the same track format), but that's a little more mechanical work than I would prefer, since this is someone else's machine.

Best regards,

Tom

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Hi, Tom,

as the wire for those Head Coils are very thin, it is likely that they may break at the soldering tabs directly at the head. It may worth a try to just heat up the Tabs for a short Moment.

Maybe it's just an idea,

best regards,

Henning

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Hi Henning,

Thanks for the tip.  These heads don't have solder lugs for connections, but rather have cables coming right out of the head.  I'll take another look, but it does not seem likely that I can do anything to resolder the internal connection.

Most likely the very thin wire has corroded near the points of connection, so if there were a way to access the connection points, it might be fixable.  However, it is all encased in metal, and doesn't look like it comes apart in any graceful manner.

Best regards,

Tom

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I removed the head and was able to take it partially apart.  What is very interesting is that the coil for each head is basically a small molded "plug-in unit."  Two magnetic "yoke fingers" protrude from the gap assembly (embedded in the brass structure) and insert into mating holes in the coil unit.

Does anyone have a coil unit similar to these?  I could even use a coil designed for a playback-only head, since the person who owns this tape recorder does not care if it records.  He only needs it for playback.  If someone has a coil unit physically compatible with this head, I could try to replace the defective coil. 

The number stamped in blue on the red coil unit is "35".  Not sure if that is important.

Best regards,

Tom

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Just an update on this project to conclude this thread:  I received another Grundig head from a different tape recorder, which I was able to retrofit into the TK64.  The replacement is a playback-only head, so the unit will no longer be able to record properly, but in this case that is fine.  The replacement head had a different mounting head, so some mechanical adaptation with shims was necessary to get the track alignment correct.  Audio quality is good, even though the head has somewhat different electrical parameters than the original head.

Thanks to all who replied,

Tom

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