Interesting question, and I look forward to reading the other responses. I expect that the answer depends strongly on whether your hamming is on HF or on VHF. I live about 1 km away from the site of
It's most important to provide a good, virtually solid, ground plane -- not only as a counterpoise for your antenna but also to shield/isolate your antenna from the AC power and all the other wiring
1. First, install a good L-C line filter such as Corcom's two-stage filter, in the TV set's line cord. It'll block both common- and difference-mode RFI. If you can't wait to find one at a hamfest, or
Where I live, you can't get a valid impedance measurement from such an instrument because its detector is broadband and detects too much power from AM broadcast stations. However, an antenna noise br
I was active (as W3JVQ) during those fabulous late '50s, especially on 10 m; but my memory has faded and I was not DXing between 1960 and 2000. Therefore I wonder whether other old-timers can confirm
I use Press Jones' no. 878 "CQ Lightning Arrestor for balanced line" <http://www.thewireman.com/ground.html> with the spark gaps opened up so they won't break down with high power and the very high V
Not sure I understand your geometry; where does the wire vertical fit into the picture? The first step is to calculate how much tension you want in the wire. IIRC, I found guidelines in the ARRL Ante
The building code in my area (eastern MA) requires 90-mph-wind survival, so I sent email to US Towers (at the address given on their website) asking whether any of their towers can survive 90-mph wi
1. It is important to put good common-mode-current RF chokes on both your coax and your rotor cables. First, right at your Yagi feedpoint put an air-wound choke coil in your coax, by winding six turn
I must disagree. It is essential! The trap is a parallel-resonant, nearly lumped, LC circuit. The C stems mainly from the capacitance between the center conductor and the shield/braid of the coax. It
The original question was: "I noticed in the ARRL antenna hand book that the braid is the input and the center conductor is the output. Is this important, and why?" I take "input" and "output" to ref
The winding on a toroid should be a single layer, not overlapping, and it should be tight; i.e., the length of cable in the winding should be as short as possible. You want to minimize parasitic capa
A G5RV is a good antenna, if you don't mind using a tuner. A G5RV works well in an inverted-V configuration, supported by a tower. A Carolina Windom could be supported by a tower at one end, but not
According to Rohn's spec sheets, either a 45G guyed tower or an SSV self-supporting tower can support an antenna having 8 sq.ft. of equivalent flat-plate area in 90-mph wind, at the top of a 70-ft. t
That's exactly what I'll do if it's not going to waste those folks' time. All I asked for here was an _estimate_. I expected that among Towertalk subscribers there'd be folks who could give me estima
I'd already done that. The difference in steel cost is not significant. The _erection_ of a 70-ft. SSV tower is what worries me. I know that a guyed system is cheaper, but by how much? $3k, $30k, or
Indeed, Rohn's documentation for the 45G and 90 mph (Dwg. no. C870478 R1) shows the upper guys for a 70-ft. tower attached at 61 ft. The antenna area spec's given in this dwg are 9.1 sq.ft. for an eq
At 7:28 AM -0700 9/3/03, Jim Lux wrote: ...I think the FCC is a bit vague on where the reference plane for the power limit is.... The FCC is (also) silent regarding _what_ power is limited. The "forw