I'm also using Phillistran guys.
I'll also try turning the booms 90 degrees. I was hoping it was not needed.
----- Original Message -----
From: "Roger Borowski" <K9RB@bellsouth.net>
To: "Jim W7RY" <firstname.lastname@example.org>
Sent: Saturday, February 14, 2004 6:16 PM
Subject: Re: [TowerTalk] New Tower up With Some Issues 2L40 TH7
> Jim, As I recall, when I had a similar setup to what you describe, I had a
> TH6DXX and a Discoverer 7.2, I had to turn the boom's 90 degrees as well
> increase the spacing to a bit over 12 feet to avoid apparent interactions.
> That was back in the 80's but I recall it pretty well. I also used
> Philistran guys, so that was not a factor. Try the 90 degree thing first
> it is easiest, but as I recall, Hygain recommended at least 12 ft.
> separation between the TH6DXX and the Discoverer 7.2 and I found out they
> were right on target. Everything worked well with that and the 90 degree
> separation of booms for me. Just turning the booms 90 degrees with 10 ft.
> spacing didn't cure much. With 12+ ft. spacing and the booms in line, 15
> meters still was severely affected for me, so I turned the booms 90
> and all was well. As I recall my spacing was a bit over 13 ft. when all
> said and done. I had IIX climbing steps on the 24 ft. mast back then but
> that was a couple of decades ago when I was much more physically fit than
> am today. Climbing that mast took a good deal of pucker power for a 240
> guy. (who's near 280 today).
> 73, -=Rog-K9RB=-
> ----- Original Message -----
> From: "Jim W7RY" <email@example.com>
> To: <TowerTalk@contesting.com>
> Sent: Saturday, February 14, 2004 8:27 PM
> Subject: [TowerTalk] New Tower up With Some Issues 2L40 TH7
> Well my 70' Rohn 45 in the air. As is the Orion OR-2800 rotator, (the
> mounting of this rotor is the coolest thing since sliced bread!!!) 21 foot
> galvanized HD steel mast, (not water pipe), a 2 element Cushcraft
> 40 meter beam (Older one) and a TH7 that I just went through and replaced
> hardware and the matching section is all new.
> Just after the 40 was put up, I checked the match with my MFJ-259B. It was
> resonant at 7.080.
> Now the TH7 just went up 9' below the 40. Re-checked the match on the 40
> it was not resonant at 7.090. Looks as if the 2 element is effected little
> by the tribander.
> Now checked the match on the TH7, I was not so good.
> The TH7 is using the "DX" element lengths.
> 20 Meters: flat at 14.090. Climbs to 1.3:1 at 14.000 and up to 2:1 at
> 15 Meters: 1.2:1 at 21.390 Never lower than that.
> 10 Meters: 1.2:1 at 28.600. above 2.5:1 at 21.100.
> This is measuring at the end of the jumper hooked onto the balun.
> The booms of the 2 antennas are parallel.
> Any input would be helpful!
> Thanks and 73
> Jim W7RY
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> questions and ask for Sherman, W2FLA.
> TowerTalk mailing list
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
TowerTalk mailing list