Blake wrote:

A common problem on old phonographs with crystal cartridges seems to be that
the Rochelle salts crystal disintegrates with humidity. I'm working on one
of these phonos now. I have an idea how it might be repaired, but rather
than reinvent the wheel, I thought I would ask how others have attacked this
problem.

It seems to me that I might be able to use a ceramic piezo element like this
one

http://www.allelectronics.com/cgi-bi...EZO_DISC_.html

to replace the old crystal inside the phono cartridge. The size is just
about right. Has anyone tried this? If so, is the output level and frequency
response comparable to the original crystal?

Or is there a better approach (that doesn't cost more than an old phonograph
is worth)?

Thanks for your comments.

1950s xtal carts sound grim and damage vinyl records, and for that
reason I would seriously consider replacing either the cart or its
innards.

Modern 1980s xtals are better but still poor. Modern ceramics are way
better. There are 3 types of ceramics, high output, medium output and
low output. If you use a ceramic as a replacement you'll need a high
output one. A medium or low output one wont give the high output levels
of a crystal.

Another option, which may spark disagreement, is a modern medium or low
output ceramic plus a fet preamp. The plus side is best sound quality
and no significant record wear.


NT