Ken Scharf ) writes:
Just got the lot of 400+ crystals I won on ebay.
Turns out they are NOT HC49/u rocks, but HC6/U!
Isn't it ture that the larger crystals are better
for use in filters than the smaller one's (higher
Q, less loss, etc?)

I have no idea. But remember other factors come into play.
Traditionally, only a handful of crystals were comodity items.
You could buy surplus, or you could get crystals for a handful
of frequencies that were premade, but generally you had to have them
specifically made for the application. I imagine (but don't know)
that such crystals tended to be better quality than a commodity crystal
from today. If nothing else, you were paying more for them.

And HC-6 holders tend to suggest something older, and hence maybe
dating from a day when more effort was put into making the crystals.
But that impression is not about the size of the holder, but about
the era of the crystal.

Of course, I've come across mass produced HC6 crystals so even then
it may be no indicator at all.

Michael VE2BVW

Looks like some fun ahead experimenting with
this and maybe a homebrew spectrum analyzer in the
works to scan around 8.3866mhz (in my test oscillator
I'm getting 8.389855mhz, better let the oscillator and
the frequency counter warm up for a while).

Time to smash some surplus 9pin tube sockets up for
crystal socket pins ....