[Lowfer] Jackson Harbor kit

Sun, 2 Nov 2003 21:43:34 -0600

Cool, I'll use that oscillator instead of the 10mc crystal. I keep the
downstairs at 20C with all my computer stuff down here and it presently is
at 19.7C since I just came in from outside and the cold air rushed down the
stairs. Now I have to get my bench cleaned off so I can actually sit in my
chair and move around!!! I see my loop needs tending to as the signal is not
up to par to what it was last winter. I'll have to pull that #8 through the
trees and get that 3/4th inch copper on the bottom run.

Mike>WE0H
http://www.we0h.us/lf
"WEOH" on 185.3026kc
QRSS 30 & -.-.  .--
FCC says 'Sufficiently powered @ 1w'

-----Original Message-----
From: [email protected] [mailto:[email protected]]
On Behalf Of Bill Ashlock
Sent: Sunday, November 02, 2003 9:33 PM
To: [email protected]
Subject: Re: [Lowfer] Jackson Harbor kit

Mike,

>Temperature stability, however, is not so great.  Claimed is +/- 3 ppm
>from -20 to +60 C.  But the curve has at least two inflections, and
>the slope is about 0.05 ppm per degree at say, 15 C.  If you consider
>decent lowfer stability to be 0.01 Hz over a half hour transmission,
>then the temperature would need to change no more than 2 C per hour.
>Most indoor living spaces conform, but many shacks are in locations
>that don't.

Thanks to Stewart's input it appears the temp stability of your oscillator
should be good enough if the converter stays inside your house.

Bill A

>From: "Stewart Nelson" <[email protected]>
>Reply-To: [email protected]
>To: <[email protected]>
>Subject: Re: [Lowfer] Jackson Harbor kit
>Date: Mon, 3 Nov 2003 03:34:46 +0100
>
>Hi Bill, Mike, and all,
>
>Here is an excerpt of post from March.
>
> > These units are KTXO-18 DIP modules by Kyocera, intended for use in
> > cellular handsets.  Comments below are based on the manufacturer's
> > spec, as well as my tests on one part from the lot.
> >
> > Nominal frequency is 12.8 MHz.  Output is AC coupled, but can drive
> > HCMOS or LSTTL by just connecting two resistors to the output.
> >
> > There is a manual trimmer but no electrical frequency control.
> > Kyocera spec is +/- 3 ppm minimum adjustment, but the actual range is
> > about +/- 20 ppm, in the usual 180 degrees, so it takes a while to set
> > it better than 0.1 ppm.  Before adjustment, the test unit measured
> > 12.8000121 MHz at 20 deg. C.
> >
> > Frequency versus voltage is pretty good.  Spec is +/- 0.3 ppm over a
> > +/- 5% change in supply.  Actual shift was only 1 Hz for 200 mV
> > change.  I would guess that most systems would exhibit a supply
> > voltage change of less than 10 mV during a half hour transmission;
> > this would be less than 1 mHz at LF.
> >
> > Temperature stability, however, is not so great.  Claimed is +/- 3 ppm
> > from -20 to +60 C.  But the curve has at least two inflections, and
> > the slope is about 0.05 ppm per degree at say, 15 C.  If you consider
> > decent lowfer stability to be 0.01 Hz over a half hour transmission,
> > then the temperature would need to change no more than 2 C per hour.
> > Most indoor living spaces conform, but many shacks are in locations
> > that don't.
> >
> > Long term drift spec is 1 ppm per year.  The test unit has been
> > connected to a counter for the past month.  During the first week,
> > frequency fell about 0.1 ppm, and then started to rise.  It's
> > presently increasing about 0.01 ppm per week.
> >
> > I found an interesting PIC-based timer that uses this oscillator at
> > http://www.picfun.com/equipj39.html .  The above page has a spec,
> > picture, and schematic showing how to drive a PIC.  If you have Win 2k
> > or XP, there should be no trouble viewing the page, otherwise you may
> > need Japanese fonts or language pack.
> >
> > I was unable to find the official spec for this part on the web.  It
> > is obsolete, since current handsets use surface mount parts.  However,
> > I believe that the KT18 series is electrically almost identical.  At
> >
>http://global.kyocera.com/frame/product/electro/ec/english/tmn/index.html
> > you can download a TCXO catalog in English.
>
>73,
>
>Stewart KK7KA
>
>----- Original Message -----
>From: "Bill Ashlock" <[email protected]>
>To: <[email protected]>
>Sent: Monday, November 03, 2003 3:19 AM
>Subject: RE: [Lowfer] Jackson Harbor kit
>
>
> > >I dug out the oscillator and it is a 12.8mc 1ppm device. Stewart wrote
>on
> > >the paper that it measured 12.799985mc.
> >
> > Mike do you know if that 1ppm is the stability, tempco (like 1ppm/degC),
> > initial accuracey, or something else?
> >
> > Bill A
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