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2012 New York QSO Party

So , New York had their QSO Party this past weekend, and while I did not get a lot of time to be on air, I did manage 40 or so SSB QSOs in the two hours or so i had to operate. I am still having mixed feelings about the new OCF Dipole I put up earlier in the spring. While the noise is better (further away from the buildings) I am losing more in line loss, just how much remains to be seen, or calculated. I tried e-mailing the tech dept of the cable manufacturer, but have not heard a reply. I am going to give them a call in a few days if I don't hear back soon.

Thoughts on the 80M OCF Dipole

So, I have had the off center fed dipole up about a week now, and one thing it definitely is, is quieter. Where the 40M/80M dipole had a lot static, due in part to being very close to the condo building I live in, the 80M OCF Dipole has much less man made noise on it. Most bands above 7 MHz are 0-1 S unit of noise, and below that there is about a 4-6 S unit reduction in noise. There is a whole lot more going on out there. I am even able to here some activity on 160M, but I think it is much too short for transmitting on 160m.

80M OCF Dipole

So... Instead of putting up a 80M Dipole I decided to put up a Off center feed (OCF) Dipole. It is a little different then a regular dipole in that it is not feed at the center, as the name implies it is feed some distance from the center. I decided to go with the 80/20 split. With this split I should be resonant in the 80, 40, 20, 10 and ?? meter bands. Not bad for about 137' feet of wire and a balun. I'll explain the construction and theory behind the OCF later, but now let me tell you about my issues getting the antenna in the air.

RF Squirrels

What are RF Squirrels? RF Squirrels are tiny little animals that love to eat RF carrying conductors. Conductors such as coax, twin lead, etc.... This weekend I was working on my 40/80 Meter dipole. I wanted to get it up another 2 meters or so, as the 'winter storm' of October 2011 did some tree trimming for me and I can reach up another 6-8 feet with a throw line. It's only up about 25 feet, a little low! When I pulled the center insulator down with the coax feed line, the coax was chewed and/or pecked in several locations. [insert pictures] I even saw some center conductor damage.

The quest for a RF Choke for a dipole

Still looking for some straight forward info on what is required to reduce the common mode current on the outside of the coax feed line feeding my 40/80M Dipole. My best choice seems to be a 1:1 wound on a torrid, but the 4"x4" box it requires would make my stealth dipoles not so stealthy. So I am looking into the ferrite beads that slip over the coax feed line. Have spent a few hours already, and still not much in the way of "use this" but a lot of goof information none the less. I will post updates when I can.

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