Hello Roger,
You may put the circuit in a waterproof plastic bag and put in the the
center of a water filled backet. Then it is sourrounded by a high
thermal capacity and should drift much slower :-) Shouldn't be a
problem for a QRP device...
73, Stefan/DK7FC
Am 05.05.2011 18:21, schrieb Roger Lapthorn:
Hi Stefan (et al)
Using the readout I have (nearest 10Hz on my FT817 and IC703) it is
very close to 137.770kHz by zero beating the signal. It would be
helpful to get a semi-local with accurate frequency calibration to
confirm the exact frequency. I may try measuring the offset from one of
the strong commercial signals and see if I can get a closer figure
although I am going away for a week so this will have to wait until I
get back.
QRSS60 would be too wobbly with the crystal/divider arrangement I
currently have. Even QRSS30 was marginal (wobbly) with G3WCB and
PA3CPM. At the moment the beacon board is just sitting on the desk in
the open air and I suspect the crystal frequency moves a few Hz (before
division) as I wave my arms typing this. There is also temperature
drift as the PA keys on. All can be much improved.
F1AFJ is not in the best direction for the loop antenna, but I am an
optimist.
73s
Roger G3XBM
2011/5/5 Stefan Schäfer <[email protected]>
Hello Roger,
What means close? Is it above 770 so i am looking for you :-) Maybe the
first RX stations can confirm the actual frequency, if unknown so far.
73, GL, Stefan
PS: QRSS60 would be more useful for all the grabbers. I see a goog
chance that you can appear at F1AFJ!
Am 05.05.2011 15:27, schrieb Roger Lapthorn:
--
http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk
http://www.youtube.com/user/g3xbm
https://sites.google.com/site/sub9khz/
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