Towertalk
[Top] [All Lists]

## [TowerTalk] finding resonant frequency of a shunt-fed tower for 160

 To: [TowerTalk] finding resonant frequency of a shunt-fed tower for 160 wa9als@starband.net (WA9ALS - John) Mon, 30 Jul 2001 12:26:50 -0500
 ```I'm interested in this too, so will jump in now. My main question now is: I have a C31XR at 72 ft - The elements are -not- grounded. Thus I assume much less (or none?) capacitance hat effect. I therefore assume I can still work out a shunt feed for -some- frequency(s), but they will likely be higher freq than if I had grounded elements and therefore more capacitance at the top? What do you think would be reasonable to shoot for with a 70 ft tower with the ungrounded elements of the C31? 40M? Maybe 80M? Doubt 160M?? Pete, I'd be interested in whatever appraoch you end up taking with your project too! Thanks ----- Original Message ----- From: Bob Alexander To: Pete Smith ; Sent: Monday, July 30, 2001 11:55 AM Subject: RE: [TowerTalk] finding resonant frequency of a shunt-fed tower for 160 > > > Pete, > Find a copy of May, 1975 Ham Radio magazine and check out the article titled > "How to Design Shunt-feed Systems for Grounded Vertical Radiators" by John > True, > W4OQ. I do not think there has ever been a better "how to" article written > about > tower matching. > 73, Good Luck > Bob, W5AH > > -----Original Message----- > > This is my ignorant question for today -- with only an antenna analyzer, > how can I determine the resonant frequency of my tower? I plan to attach a > first-attempt at shunt feed at about the 30-foot level, with 30-inch > spacing from the tower. Can I tell from the analyzer reading at the bottom > of that shunt wire where the tower is resonant? Do I need to put the > series capacitance in before attempting the measurement? Or is it all > fruitless? > > Clearly my education was neglected or I'd know the answer, so thanks for > your help and patience. > > 73, Pete N4ZR > > > > > ----- > FAQ on WWW: http://www.contesting.com/FAQ/towertalk > Submissions: towertalk@contesting.com > Administrative requests: towertalk-REQUEST@contesting.com > Problems: owner-towertalk@contesting.com > ----- FAQ on WWW: http://www.contesting.com/FAQ/towertalk Submissions: towertalk@contesting.com Administrative requests: towertalk-REQUEST@contesting.com Problems: owner-towertalk@contesting.com ```
 Current Thread [TowerTalk] finding resonant frequency of a shunt-fed tower for 160, Pete Smith [TowerTalk] finding resonant frequency of a shunt-fed tower for 160, Bob Alexander [TowerTalk] finding resonant frequency of a shunt-fed tower for 160, WA9ALS - John <= [TowerTalk] finding resonant frequency of a shunt-fed tower for 160, N2TK