[Collins] {Collins} R-388/51j4 crystal filter

[james.liles at comcast.net]

Hi Bill:
Having worked with crystals during your carrier, do you know of any source 
of low ESR crystals?  Last source I had was Mel in California but his plant 
burned down.  Frequencies in the 1.65Mc range.

Kindest regards Jim K9AXN



-----Original Message----- 
From: Bill Carns
Sent: Wednesday, September 18, 2013 7:06 AM
To: 'Richard Knoppow' ; 'Grant Youngman' ; 'Collins at listserve.com' ; 
collins at mailman.qth.net
Subject: Re: [Collins] {Collins} R-388/51j4 crystal filter

I would add something here.. Having worked with crystals in my career, you
should know that mechanical shock tends to move the crystal in frequency the
same direction that aging does.  This effect is cumulative and irreversible.
Whenever you "tap" a crystal for some reason, be sure and do it with
something soft like the end of a pencil eraser.  Sharp raps are bad.

Bill