Oh yes indeed......remember how you could change the frequency of those
FT-243 rocks? Carefully take them apart and apply a thin layer of pencil
lead. Don't remember....did that raise or lower the freq? Another
technique was to drilll a hole in the face of the rock. Put a metal screw
in it and adjust the tension on the quartz via the spring that was inside.

Ah the good ole days.

Yeah right.

Dan/W4NTI


Remember Meshna surplus had I think 4 Xtals for a buck at 7.150 which, by
using some window glass and some toothpaste, one could knock off a few
microns and shift the freq up ....only problem is that only 2 of the 4
worked after the grind ....... and that one I think was out of band ....

Definitely a second on the yeah right .....

73 Tom KI3R

garigue wrote:
Oh yes indeed......remember how you could change the frequency of those
FT-243 rocks? Carefully take them apart and apply a thin layer of pencil
lead. Don't remember....did that raise or lower the freq?

All "suspended" masses have natural frequencies and harmonics thereof.
Add mass and the freq goes down. Remove mass and the freq goes up.

Another
technique was to drilll a hole in the face of the rock. Put a metal screw
in it and adjust the tension on the quartz via the spring that was inside.

Ah the good ole days.

Yeah right.

Dan/W4NTI


Remember Meshna surplus had I think 4 Xtals for a buck at 7.150 which, by
using some window glass and some toothpaste, one could knock off a few
microns and shift the freq up

In these parts us N-Band crawlers lapped our xtal freqs up with Bon-Ami
and lowered 'em by rubbing 'em with sodder. Had pretty good success
rates both ways.

....only problem is that only 2 of the 4
worked after the grind ....... and that one I think was out of band ....

Definitely a second on the yeah right .....

Yeah, but it was an awful lotta fun.


73 Tom KI3R

w3rv