Search found 118 matches

by Andrew (grayhat)
Tue Jul 26, 2022 7:17 pm
Forum: Questions & Advice
Topic: portable antennas for 15, 12, or 10 meters?
Replies: 1
Views: 1255

Re: portable antennas for 15, 12, or 10 meters?

As the sunspots start bringing the high bands back into play, I'm curious about preferred portable antennas for 15, 12, or 10 meters. Do the compact sizes at these frequencies invite any designs that might be too long or bulky for portable use on the lower bands? Or is the EFHW still king? (Let's a...
by Andrew (grayhat)
Mon Jul 11, 2022 6:09 am
Forum: General Discussion
Topic: Why so few "random" wire antennas ?
Replies: 26
Views: 12238

Re: Why so few "random" wire antennas ?

Rob, regarding power line noise, see here

http://www.ka7oei.com/syn_blank.html#:~ ... y%20strong.

no miracles, but it may help :)

HTH
by Andrew (grayhat)
Thu Jul 07, 2022 9:27 am
Forum: Questions & Advice
Topic: Minimalist QRP transmitter
Replies: 3
Views: 1804

Re: Minimalist QRP transmitter

I've decided to go back to basics and build my dream minimalist transmitter. The fancy new computer controlled rigs are great, but I have no way of servicing them if something goes wrong, and want to spend some money with our small American companies like Far Circuits, Dans Small Parts, 3rd Planet ...
by Andrew (grayhat)
Thu Jul 07, 2022 9:22 am
Forum: General Discussion
Topic: Why so few "random" wire antennas ?
Replies: 26
Views: 12238

Re: Why so few "random" wire antennas ?

Hi Andrew, Well, that antenna farm went with the sale of my old house last year, so that avenue of experimentation is a closed chapter, and now I'm a downtown apartment dweller. However... fall is just 3 months off, and I'll be ready to go camping in the N FL woods with a spool of wire, SWR meter, ...
by Andrew (grayhat)
Tue Jul 05, 2022 3:48 pm
Forum: General Discussion
Topic: Why so few "random" wire antennas ?
Replies: 26
Views: 12238

Re: Why so few "random" wire antennas ?

I really like the idea of a random wire – OK, call it a quasi-random wire, to avoid the near 1/2 wavelength antenna lengths. However, a couple of years ago I did some A/B testing with a low-mounted dipole (i.e., NVIS), and the dipole won hands-down, both for the signal strength and for noise levels...
by Andrew (grayhat)
Fri Jul 01, 2022 6:29 pm
Forum: Questions & Advice
Topic: ATU-10
Replies: 6
Views: 2123

Re: ATU-10

Decided to return the ATU-10 when it would not match my 28.5’ speaker wire antenna. Didn’t seem to work on any band on the TR-35. It would never match my 40m doublet on 20m. I just don’t think it is a broadband tuner like exists on the LDG and Elecraft tuners. I really liked it’s features such as t...
by Andrew (grayhat)
Mon Jun 27, 2022 3:33 pm
Forum: Questions & Advice
Topic: RF "in the shack" with Random Wire 9:1 Unun
Replies: 8
Views: 2549

Re: RF "in the shack" with Random Wire 9:1 Unun

Thanks for the feedback, that seems to be inline with what I've read. I did review that website and go with the 29ft antenna wire that's suggested there as well as on the QRPguys site for their 9:1 unun. I haven't had any issues tuning the antenna on 10-40m. I think you might have keyed in on somet...
by Andrew (grayhat)
Thu Jun 23, 2022 5:42 am
Forum: Questions & Advice
Topic: RF "in the shack" with Random Wire 9:1 Unun
Replies: 8
Views: 2549

Re: RF "in the shack" with Random Wire 9:1 Unun

also, regarding chokes, here's a reference which may be useful

http://www.karinya.net/g3txq/chokes/

HTH
by Andrew (grayhat)
Mon Jun 20, 2022 11:22 am
Forum: Questions & Advice
Topic: RF "in the shack" with Random Wire 9:1 Unun
Replies: 8
Views: 2549

Re: RF "in the shack" with Random Wire 9:1 Unun

ooooh well... random wire :D first step, go here https://www.hamuniverse.com/randomwireantennalengths.html and pick one of the "good" lengths (green numbers list), that will at least ensure that your "random" won' t present a too high/low impedance on some bands; pick the length...
by Andrew (grayhat)
Sat Jun 18, 2022 10:31 am
Forum: General Discussion
Topic: VY2SW
Replies: 4
Views: 1959

VY2SW

Congrats Thomas for the Canadian license, you passed the exam with flying colors

Now... just remember to change the callsign in your rigs memories and... to change it again when you'll be back to the US of A :D