Search found 127 matches

by 13dka
Tue Jul 26, 2022 1:32 am
Forum: General Discussion
Topic: The small SWL beam (1...30 MHz)
Replies: 117
Views: 35283

Re: The small SWL beam (1...30 MHz)

as for changing the feedline routing, if you'll have a chance, it would be interesting trying the modified loop at home, while walls will cause reflections and the pattern may be distorted, it will at least tell if the backside minimum is where we expect it to be The backside minimum seems to have ...
by 13dka
Mon Jul 25, 2022 3:34 pm
Forum: General Discussion
Topic: The small SWL beam (1...30 MHz)
Replies: 117
Views: 35283

Re: The small SWL beam (1...30 MHz)

Wow, that does seem to make a difference! BTW, that's how I initially intended to arrange the feedline, that's why I was asking "what horizontal stretch?" when we discussed this first. :D But I wasn't fond of some coax permanently dangling around in the wind either, adding the pull of the ...
by 13dka
Fri Jul 22, 2022 12:21 am
Forum: General Discussion
Topic: The small SWL beam (1...30 MHz)
Replies: 117
Views: 35283

Re: The small SWL beam (1...30 MHz)

I don't have an MLA-30 but recycling its LNA might be worthwhile? No idea how good/bad it would be in a local-QRM-free environment? I have only 2 YouLoops I bought for crossloop/beam steering/QRM nulling experiments and all those plans are now becoming obsolete. :) Last night the condx had recovered...
by 13dka
Wed Jul 20, 2022 5:06 pm
Forum: General Discussion
Topic: The small SWL beam (1...30 MHz)
Replies: 117
Views: 35283

Re: The small SWL beam (1...30 MHz)

Oh, nice! I wasn't aware that it is on an equatorial orbit but I derived from the slow Doppler effect that it wasn't very close. It went below the horizon a few minutes after shooting this:




Not bad for 90mW out of a Japanese radio made in 1971! :)
by 13dka
Wed Jul 20, 2022 11:58 am
Forum: General Discussion
Topic: The small SWL beam (1...30 MHz)
Replies: 117
Views: 35283

Re: The small SWL beam (1...30 MHz)

the fact that the LNA isn't working as expected down to MW/LW is strange, judging from the NEC model, the antenna gain "down there" should be quite low and the backside even lower, so it's really strange I'll take the other one next time (I have 2 of those) to make sure the LNA isn't just...
by 13dka
Wed Jul 20, 2022 10:08 am
Forum: General Discussion
Topic: The small SWL beam (1...30 MHz)
Replies: 117
Views: 35283

Re: The small SWL beam (1...30 MHz)

Worst. Propagation. Ever. I usually don't go to the dike when the web SDRs confirm bad space weather indicators but last night I had to escape my 3000°C cozy attic apartment, so no choice. :) I was really worried the antenna is broken, or the LNA, but all SDRs up here had the same absence of station...
by 13dka
Tue Jul 19, 2022 9:59 pm
Forum: General Discussion
Topic: The small SWL beam (1...30 MHz)
Replies: 117
Views: 35283

Re: The small SWL beam (1...30 MHz)

Looks like we have a really bad radio blackout, local kiwisdr has nothing on 18 MHz either, I only hear south American stations on 20m...dammit.

Edit: A=24 right now, probably the right time to explore the FM band then 😊
by 13dka
Tue Jul 19, 2022 8:02 pm
Forum: General Discussion
Topic: The small SWL beam (1...30 MHz)
Replies: 117
Views: 35283

Re: The small SWL beam (1...30 MHz)

Out at the dike again, but condx are really bad or something is wrong, but I'm on 15 MHz and if I turn the antenna to the south I can fade the thunderstorm crackling in and out, cool stuff :)
by 13dka
Tue Jul 19, 2022 1:12 pm
Forum: General Discussion
Topic: The small SWL beam (1...30 MHz)
Replies: 117
Views: 35283

Re: The small SWL beam (1...30 MHz)

That would suggest using a 1kOhm pot in parallel with a 1 kOhm resistor, at least for experimentation. As a general SW reception antenna the almost one hemisphere wide beam is a good decision with many advantages tho, making the beam narrower is probably getting us very quickly into the "dimini...
by 13dka
Mon Jul 18, 2022 9:14 pm
Forum: General Discussion
Topic: The small SWL beam (1...30 MHz)
Replies: 117
Views: 35283

Re: The small SWL beam (1...30 MHz)

hi, first of all let me say that I wasn't expecting a full test, just some initial impressions, and then, no need to be sorry, YOU BUILT IT and took the effort of testing it, so you have all my gratitude, THANKS THANKS THANKS I have to thank you for sharing an awesome idea so I could build somethin...