Towertalk
[Top] [All Lists]

[TowerTalk] What's heating up ?

To: Topband <topband@contesting.com>, towertalk@contesting.com
Subject: [TowerTalk] What's heating up ?
From: Steve London <n2icarrl@gmail.com>
Reply-to: n2ic@arrl.net
Date: Sun, 12 Mar 2017 21:41:36 -0600
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
I am experimenting with the N4KG reverse feed method for 160 meters on a tower with a lot of stuff already on it. I like the possibility that elevated radials will be an improvement over my terrible, dry, mountaintop ground characteristics.

As I transmit, the SWR creeps up, pretty significantly. Something is clearly getting warm.

Possibilities:

- I am matching the 160 feedline with an L-network (series L, shunt C). TLW says 7 amps through the capacitor, with 3 watts of dissipation. The capacitor measures 2200 pf, the usual transmitting capacitor, cylindrical, about 3/4" in diameter.

- The M2 balun feeding the 40 meter beam on the same tower. I monitored the SWR on the 40 meter beam while transmitting on 160. No change in 40 meter SWR.

- The M2 balun feeding the KT-36XA on the same tower. I monitored the SWR on the KT-36XA while transmitting on 160. No change in KT-36XA meter SWR.

- Gamma match on homebrew 15 meter beam. Gamma match is just a piece of RG-8 dielectric/center conductor inside aluminum tubing.

Suggestions on how to troubleshoot this ? Start by disconnecting the feedlines to the baluns ? And once I determine which component is heating, what then ?

73,
Steve, N2IC
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>