If it is lightning protection and not RFI shielding that is desired, then what is done for explosive magazines ought to be enough! http://www.seftim.fr/publications/DDESB/17-3-LIGHTNING_PROTECTION_FO
snip The one experience I had with a homebrew metal window screen cage (copper or bronze, I forget which) was that it didn't work very well because the wire crossings really aren't solid electrical c
If you have the materials, why not get the easiest to model and best performance antenna? Should be great at 90'! Since survivability is one reason to avoid full size, do a mechanical analysis. If yo
Is there a reason you can't enlarge the clamp holes to take a larger diameter u-bolt? It will take a milling machine to properly move the hole center of the existing hole, but that is very easy to do
Lubricating threads makes a big difference, and here is a chart that helps http://www.portlandbolt.com/technicalinformation/bolt-torque-chart.html Grant KZ1W Lubricating the threads drastically chang
I have a Bosch demo hammer (largest hand held) for driving rods and used for much concrete demo/drilling. I made a rod driver from the shank of a broken carbide drill by MIG welding on a sch 40 pipe
see QST November 2013 page 54 review of SPE Expert 2K-FA 2KW PEP. autotuner, 6 antenna connections/memories Grant KZ1W The fact that most (not all) SS Amps have Automatic Antenna Tuners just reinforc
Jim, You're the audio expert, but didn't Bob Carver figure out some clever variable supply voltage tricks with his big Sunfire amps? I have two and my "Signature" stereo is rated 2 to 16 ohms (1250w/
Just having returned from our mini-dxpedition to Raivavae (Australs, French Polynesia) as TX5D I can confirm how loud or "only station on the band" big high antennas sound. e.g W6CCP was working Asia
I started with the KF7P arch standoff setups on two HDX589s. These are the version that hold the coax off the ground. One worked perfectly and the other I couldn't make work as the wire bundle insist
Any ferrite baluns, ununs, chokes on the feedline or at the antenna? At 2K power levels you could be heating them up (or saturating something) and changing the Z. Different frequencies will behave di
Another alternative is the Home Depot 6/4 aluminum cable, when I bought 165' for a 50amp construction drop they called it "hot tub wire". About a buck a foot, so more ampacity than #10 Cu at lower co
You are correct that ampacity is a maximum current rating. #6 Al is 0.81 ohms/kft and #10 Cu is 1.29 ohms/kft so there is a substantial difference in DC resistance indicated by the ampacity ratings (
McMaster has 1.125 by 36" depth SDS-Max. $$ but I don't think you need to go deeper than 18" - see the specs below. I think it is very important to use the specified hole diameter for the structural
If you want adhesive lined heat shrink, almost all component suppliers stock it - Mouser, Digi-Key, Jameco, Newark. I found some 5/8 4:1 at a good price at http://www.mcmelectronics.com/product/21-10
A very interesting question. I've had two verticals on metal roofs but the roofs were galvanized steel over wood frame. Thus the roof acted as an elevated ground plane. One worked very well for me wi
I had a bad pigeon infestation in a city house and was advised of two principles of deterring bird roosting - 1. Collections of guano indicates to birds it is a safe roost. So, pressure washing an ar
Contrary to other advice, do ground the tower anchor bolts to the rebar. Then you have a great Ufer ground, considering the area of the concrete in contact with the earth. The rebar should be tied pe
Interesting, welding is clearly better as it won't loosen in shipping or handling. There is a weldable grade of rebar which should be used. For small tack welds, maybe not so important. One PE told m
The Fulton K2550 seems popular but is a brake winch. After about 5 years exposure the brakes on four I had on a fresh water barge failed. Covering them might help or better yet take the winch off the