Hallo all,
The OE activity of July 31 was a joint effort of the members of the
local chapter of the OeVSV (ADL 511) in the city of Voecklabruck. As in
previous years we had our club's summer field day in Schildorn at the home
of Ossi, OE5ODL, and his YL Lydia, OE5LMO. It's a hill top QTH in JN68RF
with a great view of the surrounding country side of the Innviertel. People
came after lunch and set up several stations. There was a barbecue in the
late afternoon and a social program till late night.
At our summer field day we usually show and test the previous years
yield on finished home-brew projects. This years main activity was focused
to get on 136kHz. Our host Ossi had already set up an antenna he called
a 470 meter Marconi. Its entirely a wire antenna running 13m vertically
up a wooden pole then 40m horizontally to another wooden mast on the rooftop.
>From there it runs to a loading coil on top of the garden house with 14
turns of 16m (square coil with 4 meters on each side). From there it runs
back to the house and is connected to a 80m horizontal loop in abt 13m
height whose ends are tied together as a capacitive load. The total length
of wire is about 470 meters. As counterpoise there were several radials
laid out on the ground ranging from 20 to 100m and the lightning ground,
rain gutters and down spouts were all tied together. The site looked like
a copper mine after this installation. I will publish a drawing of this
antenna and photos from the field day on my web site <www.qsl.net/oe5eep>.
I have built the transmitter after schematics from Dave's, G3YXM, web
site <www.picks.force9.co.uk/136.htm>.
Thanks Dave for your support and all your e-mails! Without your help the
transmitter would not have been ready in time for the field day. Peter,
OE5PGL, built the VFO and added the finishing touches to my breadboard
constructed transmitter. He also built a preselector/preamplifier.
The receiver was an FT1000MP. Although one of the better Japanese black
boxes it was not sensitive enough for LF. A converter was supplied by Josef,
OE5RJL, during the afternoon and substantially improved the S/N ratio.
We also had a military surplus LF receiver of WW2 "Langwellen Anton". Although
the FT1000MP had about ten times more knobs and switches on its front panel
the 55-year-old Langwellen Anton performed better regarding sensitivity.
The plus of the FT1000MP was its filters. The station was manned mainly
by Peter, OE5PGL, but others also operated from time to time (our host
OE5ODL, OE5RJL, ...) Unfortunately I myself could not join the operation
because of family duties.
Operation started at 12.45 UTC and DJ1ZB, HaJo was our first QSO. Later
we worked DL1SAN from Ulm. There was a rather high noise level in the late
afternoon. We could hear several stations calling us but could not establish
2-way QSO's with them. If anybody has copied our signals please let us
know via e-mail or via QSL-buro.
Future activities: After some reconstruction of the transmitter, like
addition of a high-SWR-protection to the final, inclusion of adequate fuses
in the supply line (I blew a power supply when accidentally keying the
transmitter in an open load) and last-not-least putting everything in an
enclosure we will be back on the air. The antenna is still up (at least
until the next storm) and we hope to be on the air on one of next weekends.
This time we will start in the early morning hours. I also want to look
into computerized reception (want to get those fancy waterfall plots!).
We also might build a second transmitter to work from different sites.
I will inform about all upcoming activities via this list.
Questions: Does anybody know how to calculate/estimate/measure the efficiency
of our wire antenna to determine our ERP power?
Does anybody know of previous OE activities on 136kHz or is ours the
very first OE-DL contact as some of our QSO partners say?
So much for today and we'll be back, promise!
73 Heinz
Heinz Schnait, OE5EEP
Pfarrer-Schuster-Platz 1
A-4863 Seewalchen
<[email protected]>
