Hi Stefan,
You wrote:
>
> I have been 5 dB stronger than the Alpha stn on 11904 Hz at your
location ;-)
>
No, not really stronger than the Alpha's. Because the resonant loop
antenna has favourized 'your' frequency, and attenuated the HF stuff.
The antenna itself is a slotted aluminum tube bent to a ring (=grounded
shield), tube filled with 0.6 mm enamelled copper wire salvaged from
TV's degaussing coils. Inductance about 45 mH, resonated with 4.7 nF + 1
nF + the FET's gate capacity. The loop is tapped with an 2SK369 "audio"
JFET, phantom-fed through the coax. I didn't measure the antenna's
FET-loaded Q yet.
Anyway, despite that, the SNR comparison is impressive !
73,
Wolf DL4YHF
(p.s. also nice reception of SAQ here, just a bit of QRN)
Am 24.10.2010 13:56, schrieb Stefan Schäfer:
Hello Wolf,
I have been 5 dB stronger than the Alpha stn on 11904 Hz at your
location ;-) Have you thought that this will be possible? ;-)
73, Stefan
Am 23.10.2010 18:27, schrieb wolf_dl4yhf:
Stefan's 8970 Hz signal SNR was over 20 dB with 200 uHz effective
receiver bandwidth, observed at DF0WD (rural area) with a small,
resonant, active loop antenna hanging in a tree.
Screenshot here:
http://www.qsl.net/dl4yhf/grabber/2010_10_23_dk7fc_at_df0wd_200uHz_FFT.jpg
73,
Wolf DL4YHF.
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