[time-nuts] Grinding crystals...

[Burt I. Weiner]

Brian,

I remember grinding FT-243 crystals.  I had a TV set safety glass 
about 18" square and about 1/4" thick.  That and some Comet type 
cleanser mixed with water to make a thin paste would work wonders.  I 
was taught to put my finger on the corners and grind an equal amount 
on the 8 corners (4 on each side) so as not to remove the bevel of 
the quartz.  Once I applied this lesson I was able to grind crystals 
that were more stable and more active.  When I over-leaded them I was 
generally able to remove the lead using alcohol.  I've still got the 
old TV safety glass although it has an area near one corner that is 
very opaque do to all the grinding that was done in that area.  Those 
were fun days!

Burt, K6OQK


>From: Brian Alsop <alsopb at nc.rr.com>
>
>Reminds me of the FT-243 xtal controlled transmitter Novice days.  Xtals
>of the frequency you wanted were hard to come by.  We would grind xtals
>a bit on a bed of very fine abrasive to raise their frequency.
>
>The other trick was taking a pencil and adding graphite to the xtal
>faces to lower it's frequency.  You couldn't add too much or it would
>stop oscillating-- forever.  Never did understand the forever part.
>Removing the graphite didn't bring it back to life.
>
>Brian
>K3KO

Burt I. Weiner Associates
Broadcast Technical Services
Glendale, California  U.S.A.
biwa at att.net
www.biwa.cc
K6OQK