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Old April 20th 16, 05:01 PM posted to rec.radio.amateur.moderated,rec.radio.amateur.homebrew
Rob[_8_] Rob[_8_] is offline
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First recorded activity by RadioBanter: Dec 2008
Posts: 375
Default Time and Frequency References

rickman wrote:
On 4/18/2016 5:43 PM, David Woolley wrote:
On 18/04/16 15:39, rickman wrote:
How important are time and frequency references to amateur radio
operators? I've been working on a radio controlled clock design that
would be capable of generating a 32.768 kHz, 60 kHz, 240 kHz, 1 MHz and
10 MHz frequency references in addition to providing the time and date.
Initially it would be capable of receiving the 60 kHz transmissions of
WWVB and MSF. With minor tweaks other stations could be received.

Would this be useful to others?


Anyone who wants high accuracy off air time and frequency standards
would use GPS these days. Even that is almost two decade old technology
in amateur radio usage: http://www.tapr.org/kits_tac2.html


Is there something about GPS that is inherently superior for a frequency
reference? For setting a time, GPS can provide a smaller offset, but I
don't see where it has any advantages over WWVB or similar station
broadcasts where you can receive them.


The direct-sight UHF radio link provides less jitter and uncertainty
than the VLF signal that suffers from propagation effects.

The main limitation of a GPS receiver is the need for an outside antenna
for many installations. A WWVB receiver is self contained and much
lower cost.


Sure it can be easier to place an antenna for a VLF station, but on
the other hand there is much more interference, mainly from switchmode
powersupplies these days (in the old days it was from CRT computer
monitors), but also from lightning.