Search found 38 matches

by VE3EAR
Fri Sep 11, 2020 11:42 am
Forum: Antennas
Topic: Can I change the tubing diameter on a QFH antenna without having to redesign?
Replies: 2
Views: 674

Re: Can I change the tubing diameter on a QFH antenna without having to redesign?

That shouldn't be a problem. The only likely effect of the larger diameter tubing will be a small increase in the bandwidth of the antenna. That could be a good thing!

73, Bruce, VE3EAR
by VE3EAR
Sat Aug 15, 2020 1:39 pm
Forum: Antennas
Topic: Moving Room information
Replies: 1
Views: 555

Re: Moving Room information

For receive only operation, it won't matter at all which connectors you use when fabricating your extension. Depending on the brand of cables, you may find the O.D. of RG-58 (50 ohm) smaller than that of RG-59 (75 ohm), so keep that in mind when fitting the connectors. A wrap of tape may be needed o...
by VE3EAR
Sun Aug 02, 2020 2:52 pm
Forum: Antennas
Topic: Airspy YouLoop
Replies: 17
Views: 3947

Re: Airspy YouLoop

I decided that more testing of the YouLoop was needed, but I wanted to start with a clean page. I built two identical loops using some 3/8 inch heliax scraps I had on hand. Both are one metre in diameter and employ the same feed arrangement, with a balun wound on a half inch square binocular core of...
by VE3EAR
Sun Jul 19, 2020 12:43 pm
Forum: Antennas
Topic: Airspy YouLoop
Replies: 17
Views: 3947

Re: Airspy YouLoop

Anyway, the loop I built is ~5 meters wide and 1.5 meters tall. It's a rectangular square actually, with 6 turns. The bottom of the square lays on the ground. I have 2 of them set up perpendicular to each other. I'd say you've done pretty well, working with the restrictions put on you by the HOA. A...
by VE3EAR
Tue Jul 14, 2020 1:04 am
Forum: Antennas
Topic: Airspy YouLoop
Replies: 17
Views: 3947

Re: Airspy YouLoop

I think I'll throw in the towel on the YouLoop! 73, Bruce, VE3EAR I couldn't let it rest, so once again down to the workshop to try something different yet again. Since I didn't have an extra binocular core laying around, I had to make one. An old monitor cable had two cylinder-style cores on it fo...
by VE3EAR
Wed Jul 01, 2020 1:37 pm
Forum: Antennas
Topic: Airspy YouLoop
Replies: 17
Views: 3947

Re: Airspy YouLoop

The loop I made myself is at lawn-level, so despite being big it is not 'up there' where it would probably be receiving much better. From what I've read and seen on numerous YouTube videos, the height above ground isn't all that important. If you can get it up about two loop diameters above ground,...
by VE3EAR
Mon Jun 29, 2020 3:34 am
Forum: Antennas
Topic: Airspy YouLoop
Replies: 17
Views: 3947

Re: Airspy YouLoop

I tried another feed method for the DIY YouLoop today. Went with a centre-tapped 8 turn winding on the antenna side, and 16 turns on the radio side. The centre-tap connected to the shields of the loop at the feed point. Again, it worked, but it still wasn't anything to get excited over. Time to try ...
by VE3EAR
Sun Jun 21, 2020 4:35 pm
Forum: Antennas
Topic: Airspy YouLoop
Replies: 17
Views: 3947

Re: Airspy YouLoop

Perhaps the RF "sees" a different path I couldn't get your observation off my mind yesterday, and I pondered what to try to resolve this issue. Since my area of interest is receiving the AM broadcast band, along with the amateur 80M and 40M bands, it seemed to me that I would need more turns than t...
by VE3EAR
Sat Jun 20, 2020 1:21 pm
Forum: Antennas
Topic: Airspy YouLoop
Replies: 17
Views: 3947

Re: Airspy YouLoop

So what is the benefit of the Youloop's apparent twin-loop design? That's a very good question. You're correct in thinking that the shortest path, as far as DC is concerned, only has one turn in the loop proper. Perhaps the RF "sees" a different path, and takes advantage of both turns, is the only ...
by VE3EAR
Fri Jun 12, 2020 11:41 pm
Forum: Antennas
Topic: Airspy YouLoop
Replies: 17
Views: 3947

Re: Airspy YouLoop

I built my own YouLoop, but went with a different feed arrangement. Instead of using the binocular core transformer
to couple the antenna to the feed line, I opted for a current (aka choke) balun instead. It works much better.

Bruce, VE3EAR