Wow! Congratulations to this successful start up on VLF!
If i understand it correctly you have used the fence as the antenna, so
a kind of earth antenna or ground dipole? Have you measured antenna
currents or so? :-)
Will Ossi use his LF TX antenna for VLF too? :-)
It's very pleasing to see this band is coming slowly alive :-)
73 and good luck!
Stefan/DK7FC
Am 06.11.2010 10:23, schrieb Gerhard Hickl:
Dear group!
After weeks of testing and playing around with different kind of
equipment and antennas, Ossi OE5ODL has managed to transmit a signal on
VLF which is received by his grabber www.langwelle.at
It all started when we connected an car audio amplifier over a
toroid-transformer to two big fences out in the wood some weeks ago.
The purpose just was to see if we could transmit anything with this kind
of equipment. We archived about 100W of input power but nearly no signal
was radiated.
Since this time, Ossi has constantly improved his setup and yesterday
for the first time saw his signal on his grabber about 10km away from
his home QTH.
He is using his LF-antenna (20m vertical) with additional top-loads to
get a capacity of about 1200pf. The antenna is matched with some
different coils in series and for sure there is still a lot room for
improvements on the TX as well as on the RX setup. The power amplifier
is a car-audio equipment, antenna input is up to 250W.
I think this is the first noticeable signal on VLF radiated by an
amateur in OE...
Congrats to Ossi
73
OE3GHB
Gerhard
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