Hello Ed,
receiving DCF39 with 9+40dB is a very good sign. But as you mention the
large antenna will pick up a lot of strong signals causing intermodulation
in teh RX. Although bringing the antenna to resonance (by the loading coil)
will attenuate the out-of-band signals (but probably not DCF39) it will be
usefull to have an attenuator between the antenna and RX. At home, where I
use a 14m high and 22m long inv-L, I have found out that 20dB attenuation
give the best result. So with the big antenna you might need up to 40dB (a
step attenuator migh be best) , without any attenuattion you will probably
just hear a 'boiling pot'.
Good luck with the 136kHz tests, looking foward to work you in QRSS or DFCW.
73, Rik ON7YD
At 12:27 29/03/02 +0300, you wrote:
Hello rsgb_lf_group!
Last news (8z 29 mar):
- March, 28 at last have got the sanction to work to a tower and in 17z the
LF ANT already was groundless
- ANT should be simplified :
110m long
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h=~90m->----------- |<- h=131m
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150m long-> \ |
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TX O |
Wires of the ANT - Litz-wire 175x0.1 (~2mm - ekw Cu diam ~1.5mm)abt 280m
long over 5mm Polypropilene cord 470m long
- DFC39 it became audible on S 59+40 without any coil, filters, amplifiers
and ATT.
The voltage on the end (without coil)of ANT below has made ~4V
Cross-modulation is very strong.
- Now we make updating Band-pass and coil (diam ~40cm, Litz-wire
175x0.1mm abt 700-1000 mkH
- Have strengthened team Serge UA6LFQ - Let's try to organize round-the-clock
work
- If know Russian and there is a Russian coding in Windows can inform me on a
pager on http://crypt.rnd.ru for 29600 (rus or engl)
or via e-mail: [email protected] Subject: 29600 In body: text
Pager will be used in time DX-pedition
- First QSO will be RU6LWZ - call our club
73! Ed RU6LA mailto:[email protected]
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