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281. [TowerTalk] Grounding help needed (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Tue, 25 Sep 2001 10:54:47 -0400
That's one for the books! The skin depth on 160 meters in poor soil is 20 meters deep. That means a ground rod 20 meters deep would still have the some effect at the lower end, because noticeable cu
/archives//html/Towertalk/2001-09/msg00664.html (9,509 bytes)

282. [TowerTalk] Capacitor resistive values (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Tue, 25 Sep 2001 19:56:20 -0400
It depends on the capacitor. The more "bulky" or compact the capacitor for a given insulation type the lower the loss will be. The LAST thing we want is a long thin capacitor....like one made from c
/archives//html/Towertalk/2001-09/msg00672.html (8,728 bytes)

283. [TowerTalk] transmission line loss and SWR (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Tue, 25 Sep 2001 19:56:20 -0400
I picked the largest, lowest loss, 92 ohm coax in any of the dozens of catalogs I have. The reason loss is so high and power rating very low in 90-ohm coax is because the center conductor has to be
/archives//html/Towertalk/2001-09/msg00673.html (19,005 bytes)

284. [TowerTalk] Ideal 40m Wire Antenna (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Thu, 27 Sep 2001 09:43:55 -0400
Hi Tim, I'd use a dipole or an inverted V with the legs pulled out as flat as possible. Keep in mind 80 feet is a really good height for all around DX useage. If you use a loop, you lower the mean h
/archives//html/Towertalk/2001-09/msg00707.html (7,997 bytes)

285. [TowerTalk] Shunt Feed (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Fri, 28 Sep 2001 20:44:29 -0400
Z is not R. Only R=50 j=0 is a 1:1 SWR referenced to 50 ohms. Z=50 can be an infinite SWR, or perfect, or anything in between. Not in a high Q system that is changing resistance rapidly with frequen
/archives//html/Towertalk/2001-09/msg00740.html (7,663 bytes)

286. [TowerTalk] Re Tower talk Wire 4 square for 160m (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Fri, 3 Aug 2001 06:20:13 -0400
I know several people who do that. I run ropes off my 200-foot tower that hold 1/4 wl vertical elements that form a four-square for 160 meters that fires in eight directions...or I can use the tower
/archives//html/Towertalk/2001-08/msg00033.html (8,011 bytes)

287. [TowerTalk] Determining "True" Resonance of Verticals (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sat, 4 Aug 2001 21:44:45 -0400
Two things can cause that. Improper adjustment of the 259B's internal controls or external voltage coming from the antenna that upsets the detectors. There is a filter sold for HF that cures most ex
/archives//html/Towertalk/2001-08/msg00075.html (9,497 bytes)

288. [TowerTalk] Voltage or Current Balun? (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Tue, 7 Aug 2001 16:12:31 -0400
There must be some misunderstanding Bill. Current baluns are the less core-critical type of balun. By far the most core, power, and impedance critical balun is the voltage type balun. It is also the
/archives//html/Towertalk/2001-08/msg00156.html (9,431 bytes)

289. [TowerTalk] 80/40 Sleeve -- Ground (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Wed, 8 Aug 2001 11:42:45 -0400
Hi Ford, You found a good use for cattle panels. I hope they don't start turning up missing around here, if local hams start installing verticals! It sounds like your ground screen is what, 24 feet i
/archives//html/Towertalk/2001-08/msg00190.html (9,090 bytes)

290. [TowerTalk] Voltage or Current Balun? (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Wed, 8 Aug 2001 16:15:43 -0400
Hi Bill, I hope no one reaches their curie temperature....but...... I never worry about keeping beads dry. The only parts that are water problems are the connectors. Better to have air over the beads
/archives//html/Towertalk/2001-08/msg00200.html (11,507 bytes)

291. [TowerTalk] Hardline to F connector (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Wed, 8 Aug 2001 16:15:43 -0400
Hi Brian, I'm not sure where you got your numbers from, but..... At 700 MHz RG-59 (F59) cable from CommScope:6.42dB per 100' RG-6 (F6) from CommScope: 5.6 dB per 100' RG-11 (F11) from CommScope: 3.67
/archives//html/Towertalk/2001-08/msg00201.html (10,123 bytes)

292. [TowerTalk] Baluns - Primer and Questions (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Thu, 9 Aug 2001 12:36:42 -0400
This is a hot topic, judging from the e-mails. I'l eventually post something up at www.w8ji.com...but it might be a while. Just a couple more comments. No Bill, that is true. The differential mode cu
/archives//html/Towertalk/2001-08/msg00215.html (13,473 bytes)

293. [TowerTalk] Steel wool baluns (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Wed, 15 Aug 2001 11:44:01 -0400
I contacted the ARRL about that when it first appeared in the Handbook! I was amazed to see it. Steel wool baluns do not work. The ARRL has removed that balun description from their books now, after
/archives//html/Towertalk/2001-08/msg00355.html (8,273 bytes)

294. [TowerTalk] 4squares and beverages (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Wed, 15 Aug 2001 11:44:01 -0400
Hi Bob, Elevated radials radiate like crazy in close to the radial, and couple to everything around the radial. There is nothing you can do about that radiation, it always happens. Remember what cau
/archives//html/Towertalk/2001-08/msg00356.html (8,715 bytes)

295. [TowerTalk] Steel wool baluns/no review (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Wed, 15 Aug 2001 22:00:02 -0400
This goes to the earlier discussion about unedited and unreviewed technical text. Look at how this can happen in the only publication system that actually attempts to review things! Now consider the
/archives//html/Towertalk/2001-08/msg00369.html (8,676 bytes)

296. [TowerTalk] Wattmeters and 75 ohm Coax (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sun, 19 Aug 2001 14:08:09 -0400
The line section has a surge impedance of 50 ohms, and the slugs are nulled at 50 ohms. You could re-null the slug at 75 ohms, assuming it has enough range inside. I have no idea if Bird does this,
/archives//html/Towertalk/2001-08/msg00427.html (8,897 bytes)

297. [TowerTalk] Shortened 80m dipole/inverted vee (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sun, 19 Aug 2001 14:08:09 -0400
Hi Tom, You've received many good answers, but keep this in mind: You are generally better off to use lumped loading rather than feedline loading, of you are worried about getting every last watt out
/archives//html/Towertalk/2001-08/msg00428.html (8,434 bytes)

298. [TowerTalk] Wattmeters and 75 ohm Coax (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Sun, 19 Aug 2001 19:21:44 -0400
Woops! The prototype 259B I have is not the 259B that is production. Mine is a transition unit to the 269 which is 16-bit and has more memory and does more or different things. Sorry about that. 73,
/archives//html/Towertalk/2001-08/msg00433.html (8,112 bytes)

299. [TowerTalk] Ladder Line and Coax (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Tue, 21 Aug 2001 09:32:10 -0400
Hi Dave, The problem is with feedline balance and/or distance to the feedline. The most effective type of balun is a 1:1 chokebalun....and it belongs on the OUTPUT side of the tuner...not the input.
/archives//html/Towertalk/2001-08/msg00477.html (10,626 bytes)

300. [TowerTalk] ladder line balance (score: 1)
Author: W8JI@contesting.com (Tom Rauch)
Date: Wed, 22 Aug 2001 06:57:55 -0400
It is not a valid test. Radiation comes from charge acceleration, which is related to current and distance (ampere-feet). There also are induction effects caused by voltage (charge distribution) and
/archives//html/Towertalk/2001-08/msg00498.html (9,472 bytes)


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