Genosse Roman, LF,
Yesterday i built a small LF PA providing 10 W at 50 Ohm. It consumes 1
A at 12 VDC. I intend to run an over-night WSPR-2 transmission (20% TX
rate) on saturday night, using the ground loop or earth antenna in
JN39WI. The signal generator is a Raspberry Pi running on a separate 7
Ah lead gel accu. The PA has its own 7 Ah accu. The PA can switch from
2.5 W to 10 W :-)
Will someone catch the signal at all? At least i'm already asking for RX
stations!
I'll carry some measuring equipment there, like my M0BMU LF tuning
meter, some Cs, a T106-2 and some wire, also a small ferrite core to
build a transformer if necessary.
What could the feed point impedance be? I have no idea! My modified
MFJ-259B covers LF but i expect it will be overloaded with strong
signals on the antenna, so i try to match the antenna with the transmitter.
More soon :-)
73, Stefan
PS: Oh, i'm also going to connect two anti-parallel LEDs to the antenna
to see if they shine. It is all a big game for old children!
Am 05.09.2018 23:54, schrieb Roman:
OK Stefan.
Try it to do. may be wonderful results.
Roman
Hello Roman,
Yes maybe i'll build a quick PA tomorrow for LF and will transmit on LF
for 24 hours, each 10 minutes, WSPR-2. I have no idea at all how this
antenna performs on 137 kHz. Is it still a loop or rather a dipole or a
mixture? At least it has about the length of a full size dipole for 137
kHz. I would TX at 10 W RF power only, so that a small accu covers some
hours. But i'm not yet sure if i can find the time to do it tomorrow.
73, Stefan
PS: If the antenna acts as a dipole, then it is beaming to Russia directly.
Am 05.09.2018 21:42, schrieb Roman:
Congrts, Stefan!
We are follow by your success!
Listen, do you planning to operate 136 kHz, I hear, tell me pse - do you
planing try to TX with that ant on 477 kHz and 160M?
I will be interestin to hear about results.
73!
Roman
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