I have the March 63 QST and can email copies. Guess I'd never build it of used well casing unless I was placing it where it would do no harm when it collapses, because I haven't the equipment to test
1500 watts at 50 ohms gives 274 volts. That could be 548 volts if the SWR is 2:1. Current at 1500 watts and 50 ohms is 5.5 amps, 11 amps at 2:1. Give them a fair margin for reliability, as much as 2:
Hi, Tim; The cross won't hold a self supporting upright reliably in all soils, and it might be marginal on supporting the downward force on a guyed tower. Supporting downward force requires sufficien
Hi again, Tim; I forgot to mention a temporary base I built for a self-supporting tower several years ago. It consisted of 4 treated timbers standing in the ground several feet apart, to achieve a fa
It may be a breakdown of insulation somewhere in the system, associated with the higher voltage at higher power. Does it happen on one or more bands but not all? Only at certain frequencies? Breakdow
Capt. Paul Lee, Vertical Antenna Handbook, described using aluminum irrigation tubing. It comes in 30' lengths and, while nowhere near as strong as 6161, it is relatively inexpensive and works well f
Hi, David I guess you refer to the antenna modeling course. I was very pleased with it. I had used EZNEC and ELNEC for many years. In the course, I learned more about the limitations of NEC2, learned
Although the large vent opening is handy for running feedlines and control cables, it is not ideal for the ground line. The ideal ground line should be wide, to minimize inductance. Commercial statio
Hello to all; Please advise me regarding methods and materials to support coax going up a tower. Problems I recognize include: Overstressing the coax or the connector - I assume this is resolved by a
When tuning while transmitting, tune to minimum reflected power. As it approaches zero, you may go to maximum sensitivity or low power on the meter, but remember to turn it back to high power so you
Chuck is correct regarding the direction of stresses, and that the pier must be fastened to the base or it will overturn on top of the base. However, it is not difficult to achieve that with the re-b
Hi, Chuck; You are correct on both points. The moment arm I mentioned is correct for the righting moment created by the weight of the pier and structure on it. The moment arm for the re-bar is the di
I am also looking for ring terminals suitable for ground radials, something less expensive than insulated crimp-on terminals, for 1/4' studs and multiple #13 wires. I also wish information about usin
Thanks, Doug; McMaster-Carr has many styles of ring terminals. Don't know why I didn't think to check there first. 73 de WOØW To: <towertalk@contesting.com>
6. Divide and Control Greetings to all; The following is copied from: http://lightning-protection-institute.com/lightning-protect.htm Are ten radials and 80 ground rods absolute requirements? No! The
Hi, Jason; Independently grounding each tower leg provides parallel paths to dissipate the lightning charge and thus reduces the impedance and the maximum voltage developed. (V = I Z) Wide straps off
I certainly agree with Jon Ogden, NA9D, on all points except the application of anti-corrosion compound. Mechanical joints require application of appropriate anti-corrosion compound. They also requir