[Hallicrafters] 10 mHz xtals

[RICHARD SOLOMON]

Today, one can buy a GPSDO for around $100 or less. This "locks" a 10 MHz

(or other freq) oscillator to the GPS signal, resulting in accuracy that far

surpasses anything the regular Joe can get his hands on. Cesium Standards

and Hydrogen Masers are a tad pricey.

 

I use one GPSDO as the reference input for my counters (yes, plural) to get a

more accurate reading than any counter based reference could supply.

 

Google GPSDO or check "the dark side" and see what's there. My last buy was

a Lucent 15 MHz GPSDO for $78.

 

73, Dick, W1KSZ
 
> Date: Mon, 16 Mar 2009 12:50:26 -0700
> From: gzook at yahoo.com
> To: daileyservices at qwest.net; hallicrafters at mailman.qth.net; km1h at jeremy.mv.com
> Subject: Re: [Hallicrafters] 10 mHz xtals
> 
> 
> 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.
> 
> 
> 
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