At 09:30 PM 6/3/2003 -0400, Eric Scace K3NA wrote:
If folks are particularly interested in frequency accuracy, a recent
issue of "QEX" discussed how to setup a GPS-slaved time &
frequency standard. A readily available surplus unit (used in the
cellular telephone industry) was featured in the article. The
unit provides a high-accuracy 10 MHz signal and time-of-day. These have
been advertised in "QST" and "QEX" for about $265 over the
last year or so. Achieving a stable and accurate local standard based on
this little rack-mount box would be much easier than
WWV-based solutions.
I use one of these with my RX-340, where it literally is a plug-n-play
solution.
A very ambitious person would devise a system for slaving the Orion
TCXO to an external 10 MHz standard.
I have used double-oven 10 MHz local standards (also retired from the
telecommunication industry) whose accuracy was tracked
against WWVB at 60 kHz with a chart recorder. This approach is accurate
enough to observe the daily aging rate of the crystal
(after a few days of measurements). A WWVB-based calibration mechanism
would also be quite accurate, but it does require a recorder
and more time. The GPS-slaved system is much faster, which is why it is
in common use today.
-- Eric K3NA
This receiver seems to be a single oven but is highly accurate and has
low phase noise. Software beyond the basic SCPI command set can be found
at http://www.realhamradio.com/gpscon.htm to control as well as chart
accuracy over time.
The receiver itself is available from www.buylegacy.com and at $249 is
a no-brainer when compared to the $4k rig it is used with. The manual
is online at buylegacy.
Eric
--
Eric F. Richards
efricha@dimensional.com
"The weird part is that I can feel productive even when I'm doomed."
- Dilbert
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