[Hallicrafters] 10 mHz xtals

[Glen Zook]

The chances of any crystal being "exactly" on frequency are not that good.  That is why frequency standards have frequency "netting" adjustments.  When used for something like a filter then the absolute frequency of the crystal definitely comes into play.

For those who don't understand the term "netting":  It is an "olde tyme" two-way radio term which means to adjust the transmit and/or receive frequency to the desired frequency.

I am using one of the 10.000 MHz clock crystals in a frequency standard that I use for checking frequencies on various VHF/UHF amateur bands.  I need to get around to adding a 7490 I.C. to get markers every 1 MHz.  To make sure that everything is "right on frequency" I "net" the frequency to WWV.

Also, I use the clock crystals in various receiving converters and in most of them the frequency can be altered a little by simply adjusting the the oscillator tuning slightly.

Glen, K9STH

Website:  http://k9sth.com


--- On Mon, 3/16/09, Carl <km1h at jeremy.mv.com> wrote:

And maybe a few in a 100 will be exactly on frequency. I used to buy those in bulk and then select values for 4 and 8 pole filters. I was amazed at the variance but sold several hundred matched sets for about 10 years through Radiokit.