Dick,
3579.25 kHz crystal (very common TV colour decoder frequency) divided by 13
then 2 (26 times) will give you 137.663 kHz, which can be pulled +/- 30 Hz
or so. This is what I use. You need an 74LS161 and a half a 74LS74 or CMOS
equivalents. Dead easy!
73, Dave G3WCB IO91RM
-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of Dick
Sent: 18 August 2006 21:07
To: [email protected]
Subject: Re: LF: QRSS QRG's
Ok thanks, hmmm unfortunatly I am a bit late in discovering this, as I
already made the first part of an X-tal oscillator for 136.320kHz........
Well, I guess I have to start looking in my X-tal again.
Problem is how to make 137.7 (or better 137.7x2) from
an X-tal.
Of course I have nothing in my junkbox that can be divided to this
frequency, in fact
even for 136.320 I had to manually modifiy an X-tal by opening it up and
painting it.
Anyway, meanwhile I got QRSS running!
Now I only need to built something that creates the right fixed
frequency....
My VXO will reach it, but is not acurate enough , I guess.
73
Dick, PA4VHF
QRV tomorrow 14-15 utc in beacon mode around 136.550kHz with 8wpm.
QRSS activety to follow soon, I hope.
Unfortunatly I can't listen, because band is blocked by heavy QRM/QRN from a
light dimmer somewhere in
the neighbourhood......
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