Hi Walter and group,
Ok - crossband switching was also a problem here (at DF0WD).
I have solved it with an additional 'auxiliary' antenna dedicated for
MF. Maybe you can put up something similar for 80 or 40 meters :
http://www.qsl.net/dl4yhf/mf_reception/MF_Reception.html
(contains a photo of the MF reception setup used last weekend at DF0WD.
The coil is a bit oversized for reception, but who knows... one fine day
we may be allowed to transmit on MF in Germany, too ...)
All the best,
Wolf DL4YHF .
Am 15.04.2012 21:19, schrieb Walter Staubach:
Wolf,
my progblem is - I have only one wire for 600m, 80m and 40m. So
switching with all the inside- and outside coils and tuning takes a
lot of time. I think it is the same with DI2AF.
73
Walter DI2AG / DJ2LF
----- Original Message ----- From: "wolf_dl4yhf" <[email protected]>
To: <[email protected]>
Sent: Sunday, April 15, 2012 1:40 PM
Subject: Re: LF: Titanic acty
Greetings all,
Nice activity on MF last night. Would have liked a bit more crossband
activity (especially from the DI stations) but none of them seems to
have been active for xband QSO with those poor fellows without tx
permission on 500 kHz.
I could significantly improve the rx quality at the club station
(DF0WD) so a couple of QSOs was possible with "armchair" copy this
end (rx on MF). Thanks everyone involved, especially Finbar and Graham.
The big difference was a large resonant tuning coil (which will one
fine day be used as a loading coil). 20 cm long, 15 cm diameter, 60
turns of 1.8 mm enamelled copper wire neatly separated by a plastic
wire ("Maurerschnur" in german, can't translate that into english). L
approx. 320 uH, and Q at 500 kHz about 500 (calculated). The
primary's ends were connected to a 10 meter vertical wire, and the
"MF earth" on an earthstake located as far away from the shack and
mains as possible. A secondary winding with few turns (tapped for 50
ohms) acted as insulation between "shack earth / mains ground" and
"antenna earth", spaced a centimeter above the primary coil layer.
When connecting "ground" and "antenna earth", there was tremendous
QRM (only OK2BVG, G3KEV, and IQ2MY audible). With separate grounds,
DI2AG, DI2AF, DI2AM, many UK, PA and OK stations were nicely audible
after sunset.
(crossband) QSO were made with EI0CF, GB100MGY, OK2BVG, IQ2MI. Sorry
to have missed you Mal, you were very solid copy during your QSO with
Finbar.
All the best,
Wolf
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