Search found 275 matches
- Fri Jul 08, 2022 12:43 pm
- Forum: General Discussion
- Topic: The small SWL beam (1...30 MHz)
- Replies: 117
- Views: 77117
Re: The small SWL beam (1...30 MHz)
Another note, I forgot to write that the antenna SWR curve "flatness" is also dependent on the diameter of the conductor, in the model I left the diameter to 5mm (0.00250m radius) as for the Matt Roberts (KK5JY) "SRL" antenna, lowering the wire diameter to 2.5mm will cause the SW...
- Thu Jul 07, 2022 3:33 pm
- Forum: General Discussion
- Topic: The small SWL beam (1...30 MHz)
- Replies: 117
- Views: 77117
Re: The small SWL beam (1...30 MHz)
update: ran some tests and, slightly changing the length of the side it's possible to relieve the FM band "issue", by shortening the side to (about) 65cm or lenghtening it to (about) 80cm the gain in the 70...120 MHz range goes back to negative and may avoid issues with FM "blowtorch&...
- Thu Jul 07, 2022 12:44 pm
- Forum: General Discussion
- Topic: The small SWL beam (1...30 MHz)
- Replies: 117
- Views: 77117
Re: The small SWL beam (1...30 MHz)
:( I hope this is nothing serious and that you'll get better soon! I hope that too, and hope it will be over in a while, but let's move on :) 1. Height flattens the lobe but above 14 MHz, it looks like more than 3-5m can have the opposite effect: You're further confirming my observations, to mantai...
- Thu Jul 07, 2022 8:12 am
- Forum: General Discussion
- Topic: The small SWL beam (1...30 MHz)
- Replies: 117
- Views: 77117
Re: The small SWL beam (1...30 MHz)
as for height effect on this antenna this first image shows how the pattern changes when we change the antenna height https://i.postimg.cc/tJs1JjdH/dirloop01.png as you can see, raising the antenna we lower the radiation lobe so cutting off more and more the sensitivity to high angle signals while i...
- Thu Jul 07, 2022 7:25 am
- Forum: General Discussion
- Topic: The small SWL beam (1...30 MHz)
- Replies: 117
- Views: 77117
Re: The small SWL beam (1...30 MHz)
Hi Andrew, Hi there, Ollie :) ! This is super exiting! I meant to comment on your cardioid loop thread but my reply would've created a new page and pushed your great post to the previous one. What I meant to comment on that thread is that the "cardioid loop" concept looks particularly pro...
- Wed Jul 06, 2022 3:19 pm
- Forum: General Discussion
- Topic: The small SWL beam (1...30 MHz)
- Replies: 117
- Views: 77117
The small SWL beam (1...30 MHz)
The image below (full size HERE ) contains all the infos needed to build a small loop antenna, fitting even in restricted spaces, which will offer an "unidirectional" lobe like the one from a "beam", the lobe is mantained from a few KHz up to above 30 MHz and allows to "null...
- Sun Jun 26, 2022 3:43 pm
- Forum: General Discussion
- Topic: ARRL Field Day this weekend!
- Replies: 5
- Views: 5784
- Sun Jun 26, 2022 12:19 pm
- Forum: General Discussion
- Topic: ARRL Field Day this weekend!
- Replies: 5
- Views: 5784
Re: ARRL Field Day this weekend!
well, don't complain too much, it may become worse
https://www.sciencealert.com/a-giant-su ... t-at-earth
it all depends from the direction of that sunspot
https://www.sciencealert.com/a-giant-su ... t-at-earth
it all depends from the direction of that sunspot
- Wed Jun 22, 2022 4:52 pm
- Forum: Questions & Advice
- Topic: New to SDR - Tips and advice, please
- Replies: 1
- Views: 14143
Re: New to SDR - Tips and advice, please
start here
https://swling.com/blog/tag/msi-sdr/
let aside the receiver, most infos will fit, then proceed here
https://swling.com/blog/tag/linear-loaded-dipole/
and then... we may ragchew about antennas and more
btw, welcome to this hideout
https://swling.com/blog/tag/msi-sdr/
let aside the receiver, most infos will fit, then proceed here
https://swling.com/blog/tag/linear-loaded-dipole/
and then... we may ragchew about antennas and more
btw, welcome to this hideout
- Tue Jun 21, 2022 3:56 pm
- Forum: Log Sharing & Broadcast Frequencies/Schedules
- Topic: frequenze BBC Antartic Midwinter.
- Replies: 4
- Views: 30153