[TenTec] High stability frequency reference oscillator for theOrion II

[Kim Elmore]

I, too, would be interested in this. I reiterate Ron Castro's 
comments. Also, I would need to know just how "plug in" this mod would be.

73,

Kim Elmore N5OP

At 01:27 PM 12/31/2009, you wrote:
>I would be very interested in participating, and yes, I believe the
>"original" Orion used the same oscillator.  While the mod on my website
>mitigates the problem considerably, it can't really cure it.  Looking at the
>spec sheet of the AOCJY, it appears to be available in the correct operating
>voltage, excellent phase noise. The sine wave output is shown at +2 dBm @ 50
>Ohms output load while the original shows 1 V P-P into 10 k Ohms.  This
>should probably be looked into.  Here are the specs of the Siward (I just
>noticed my website link needs to be changed):
>
>http://www.datasheetarchive.com/TXO32-datasheet.html
>
>Another minor problem is that the AOCJY appears to be an SMT device, so some
>sort of PC board would need to be designed to convert the architecture.
>That would be good though since the AOCJY accommodates an external
>adjustment pot that should make calibration a breeze.  Also because since
>its an oven-controlled device, an external 5 or 3.3 VDC regulator/filter
>will be needed along with a direct connection to 13.6 VDC so the oven stays
>on when the power switch is off.
>
>BTW...did you ever notice that most new Orions are 20 Hz off frequency on 20
>Meters?  I heard that regularly on the TT Sunday net when I first started
>checking in.  That's apparently because when they are adjusted at the
>factory, the radio is upside down with the cover off and the compartment is
>at room temp.  Normally that compartment gets to over 100 degrees F without
>the fan mod!
>
>A friendly call to TT might be in order to see if these specs will work, and
>once done, you should have no trouble finding ten folks who want go in.
>
>             Ron  N6IE
>        www.N6IE.com
>
>----- Original Message -----
>From: "Linwood Davis" <linbdavis at earthlink.net>
>To: <tentec at contesting.com>
>Sent: Wednesday, December 30, 2009 7:16 PM
>Subject: [TenTec] High stability frequency reference oscillator for theOrion
>II
>
>
> > 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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> >
>
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