Keeping it on would fix the problem...but I'm sure it would eventually take
its toll on component life. I ran across a Peltier device while I was
researching this, and very briefly considered pursuing that, but it was a
bit to sophisticated and costly, but a good idea anyway!
Easy enough to retune to the other station's frequency if they are off 20
Hz, but during a net it's kind of a drag tuning up and down all the time :-]
Ron
N6AHA
----- Original Message -----
From: "Bill Tippett" <btippett@alum.mit.edu>
To: <tentec@contesting.com>
Sent: Monday, February 20, 2006 6:09 AM
Subject: [TenTec] Orion II Frequency Stability Progress
N6AHA:
>Greater stability can be achieved using more sophisticated
temperature control, including keeping the area warm even when
the radio is off, or using a crystal oven
...or simply leaving the power on continuously.
I previously worked at HP where we sometimes used Peltier devices
for oscillator temperature stability
in high precision digital voltmeters (A/D techniques
convert V to F so oscillator stability is important
for ppm range voltage accuracy). You might be able
to mount one of these directly to the crystal can.
http://www.peltier-info.com/
>however, for most purposes, this should give the kind of
stability needed to prevent being 20 Hz high or low on a net
(I heard several stations off by at least that much on the
Ten-Tec net today, a couple of them using Orions), which is
noticeable on SSB.
...which begs another question. If you can hear that
you are off frequency by 20 Hz, why is ppm accuracy even
necessary in the first place? ;-)
73, Bill W4ZV
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