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Blake Blake is offline
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Default Repair of Crystal Phono Cartridges ?


"Ross Herbert" wrote in message
...
It must be a pretty big cartridge if it will take a 15mm diameter
ceramic disc. In my experience, the crystal/ceramic element in a phono
is quite small so I think you are not going to have any success in
repairing it. The elastic suspension carrier for the element might
have deteriorated as well so you will probably find this a problem.

Not to put too fine a point on it, why not just buy a new ceramic
cartridge and save all the hassle? Though looking at some of the
prices here http://www.turntableneedles.com/brow...cts/Index.html
you might not like it.



Thanks for the reply.

Actually, I've already examined the failed cartridge. The old crystal seems
to be a slab about 15mm long and 10mm wide, fitting into a space 15mm wide
and 25mm long inside the cartridge shell. I thought I might be able to grind
the sides of that circular 15mm barrium titanate piezo on a belt sander to
adjust the fit. Or if it shatters on grinding, find a slightly smaller one.

My old crystal was clamped into the cartridge by two rubber blocks, one
glued to the top shell and the other to the bottom. The gap between measures
about the same as the crystal thickness. Are these what you mean by the
elastic suspension carrier? There was also a thin, crumbly black coating on
the white crumbly crystal. I took this black coating for a conductive
electrode, but if this is an elastic suspension, then I might need to
understand its function better. Maybe the barrium titanite can go without a
coating. Or I could dip it in the kind of liquid rubber they sell for
coating tool handles. This point bears some more consideration.

As for buying a new cartridge, well . . . You guessed right about my
willingness to invest cash in the project. This phono isn't a fine antique,
and would probably not fetch more that $25 after I finish the repairs. But
more importantly, I wouldn't learn anything or have any fun by hiring a
specialist to do the job for me. And we're all in this for the fun of it,
aren't we?