Hello folks,
Primarily for the reason below, I've been considering drastically
reducing the frequency drift over temperature that my Orion II
experiences. So I contacted Abracon Corp to see if they'll make a few
44.55 MHz high stability oscillators to replace the original one with.
I'm interested in the AOCJY series oven controlled crystal oscillator,
which has remarkable stability. Try 5 parts per billion stability! (over
0 to 50C). That'd be three orders of magnitude better than the original!
Anyway, I know they won't make just one for this mere hobbyist, but
hopefully, they'll consider making 10.
So I'm here to see if any Orion owners would be interested in also
purchasing one. I got a informal quote of $135 a piece so far.
Also, I don't know, but does the Orion (565) also use this frequency
reference? Or any other Ten-Tec radio? I see from the O II schematic
that the Sub Rx uses a divided-down signal from this same oscillator. If
I remember right, the Sub Rx design is the same as the Jupiter Rx.
(Please correct me if I'm wrong.) If so, are there any Jupiter owners
that may be interested in joining this oscillator purchase?
So here's where the drift becomes annoying:
Recently, I begain "watching" meteors with my Orion II and DL4YHF's
Spectrum Lab software. What I do, actually, is tune to 14.670 MHz (CHU
Canada), and observe CHU's signal. Using Spectrum Lab's waterfall to
display a 50 Hz swatch of spectrum around the carrier, I can see when
micrometeors and not-so-micro meteors strike the ionosphere between
here, NH, and there, Ottawa. Normally, the signal is fairly weak, so
when a meteor ionizes a trail in between here and there, the signal
strength significantly increases. What's more, the resulting spectrum is
often composed of curves and lines above and/or below the carrier
frequency. I believe these are created by the doppler shift due to
ionospheric winds. (Why do I do this? Hey, I'm a curious guy, what else
can I say?)
The trouble is, especially just after turning the Orion on (and for the
next 30 to 45 minutes), the frequency drifts by as much as 10-15 hertz.
Normally, you probably don't notice this, but when narrowed down to a 50
Hz display, it looks bad! (See AA6E's site,
blog.aa6e.net/2005_08_01_archive.html, or N6IE's site, www.N6IE.com, for
addition drift info.)
Let me know,
Thanks,
Lin
WB1AIW
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