Hello Steinar,
Am 20.07.2012 11:43, schrieb Steinar Aanesland:
Hi Stefan
Is this the MFJ 259B HF antenna analyzer modification?
http://www.we0h.us/Amateur_Radio_stuff/MFJ/MFJ-259B/LF-MF-Mods/
la5vna S
Yes, this it is! Well documented by a few images. For LF i used a 10mH
fixed inductor (looking about like a resistor) and for MF i took a
FT50-77 and about 30 turns or so. A fixed inductor would work as well i
think. Just insert it and see what the range is...
73, Stefan/DK7FC
Fra: [email protected]
[mailto:[email protected]] På vegne av Stefan Schäfer
Sendt: 19. juli 2012 01:55
Til: [email protected]
Emne: Re: LF: 630 meter full size dipole
Hi Jay,
Interesting, thanks for the info!! Yes and that could be a real
alternative for those with a small garden and a stressing XYL. The wire
for the dipole can be quite small and fits into a backpack.
Then its a question of the dependency of the antenna efficiency as a
function of the ground conductivity. This will be one of the interesting
results!
10m above ground is not much for a 630m band dipole but if the
difference to 2m above the ground is just a few dB, one can easily
through out the wire during taking a walk and can do some MF /p
operation, without a kite, without the need for a free field, without a
tower, without a good earth (connection)... Many advantages! Maybe...
BTW i have also modified (extended) the range of my MFJ 259B HF antenna
analyzer to cover MF (313...658 kHz) and LF (103...209 kHz). This
modification is done very easy! I'm not sure how accurate the
measurements are in that range but maybe it gives me some ideas "where i
am".
Looking forward to that test!
73, Stefan/DK7FC
Stefan
This may be of interest for your next exploit ...
Looking back in my 500 kHz log, I see that on 1/3/2010 I had a CW QSO
with WD2XSH/35 in South Dakota ... who was running a full size 600 meter
dipole. As I recall his antenna was relatively low at 30 or 40' above
ground and he was running only 50 or 100 watts. His signal was weak but
solid copy over the few nights that he was active. Distance was 1210 mi
/ 1950kM. Believe his antenna was 'out in the open' as he apparently
owns a good sized farm.
Jay W1VD WD2XNS WE2XGR/2
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