Interesting -- I'd assumed Rich was referring to the W2DU bead choke type. I know they have some reported deficiencies at low frequency due to uneven heat distribution along the string of beads, but
Tom, I think you're getting the horizontal and vertical polarization cases mixed, with maybe also a little too much focus on the 160m case. In his book, Dave Leeson observes that ground characteristi
73, Pete N4ZR Sometimes a tower is just a tower ________________________________________________________________________ Where do you get ICE bandpass filters & beverage matching boxes? The same plac
I just acquired a Butternut HF9V, and would like to give it the stealth treatment. It has large aluminum wire inductors for loading on 80 and 40. As long as I maintain electrical continuity, would a
I don't think you read my whole message. Modeling with NEC has been used to compute the effect of aircraft carrier superstructure in the vicinity of antennas, so I don't think what you describe is ou
Mel, it doesn't make physical sense. That could be April Fools, or it could be 73, but it ain't real. And I don't work for NSA. 73, Pete N4ZR Sometimes a tower is just a tower _______________________
baluns. I do the same. At least at CW/SSB duty cycles, they have held up very well at ~ 1300 watts on 80m. I'm not 100 percent sure there's enough inductance for 160 meters. For those who don't want
Until you try to model the shunt feed attached to a cylindrical model of the tower. Then the unequal diameters connected at an acute angle give wildly improbable results. Thanks to K6SE for straighte
I have had very good luck using the Budwig RF-1 dipole center insulators in my 80m array, with 50 #73 beads over Teflon coax and PL-259s on each end. I use big black plastic tiewraps, looped over the
Because my antennas were already up, I elected to try low power and leave the elements ungrounded. At 200w, so far so good. I am wondering, though -- if and when I go to high power, should I expect t
Sorry, I wasn't thinking clearly. That makes perfect sense. I must have crossed the two ideas from your earlier post. Just for fun, I ran my whole-tower model with a zero-current source at the juncti
Just a footnote -- I ran the same model with 2000 watts input, and the model showd ~1250 volts across the 40m yagi insulator. Intuitively, enough to be concerned about, particularly if the insulator
I'm a little leery of serendipitous resonances and unexpected interaction that could result if you short elements and boom together. Wouldn't it make better sense to connect a small inductor between
I believe they have said that this is a possibility, since it should not affect the operation of the antenna on its design frequency. Given the high voltages present, I assume that a vacuum latching
The first time out, though, these caps are awkward, because they are hard to adjust. 73, Pete N4ZR Sometimes a tower is just a tower __________________________________________________________________
My Klein harness/belt is two separate systems, interconnected at the waist belt. The waist belt could function by itself with the positioning lanyard should the full-body harness fail, and the fall-a
A lot of people may disagree, but I always use both my fall arrest lanyard (the one that attaches to the harness in the middle of my back) and my positioning lanyard. When climbing, I hook the positi
I notice that Digi-Key is selling CAT-3 network cable for $72/1000ft. It has 8 #24 conductors, which suggests that at least for my run (~200 ft.), it can be used with TopTen relay boxes with minimal
I normally wear leather gloves on the tower, particularly while climbing, and have not found the OSHA clips on the Klein fall-arrest lanyard to be hard to manipulate. In fact, they have something clo
To: <towertalk@contesting.com> Wait a sec -- the physics don't compute. If you have the fall arrest lanyard hooked above your head somewhere, you will only fall a couple of feet before it takes up th