On the transmit side at a commercial broadcast facility, they probably design so that they can use open balanced pairs or quads. Look at the pictures of VOA transmitters and you see open balanced pa
Presumably this is to replace the openwire line you're currently using? Dielectric losses aren't all that significant at HF frequencies (except, perhaps on 10,12,15 m, but even there...) unless you'r
I don't know that it has.. I see lots of lightning rods around in "lightning country" (FL, NM, CO, etc.).. not many in CA, it's true, but we don't see much lightning here.. Strapping to hold things i
bear in mind also that the tower is made of steel covered with zinc, hardly the conductivity of copper. Lower conductivity means greater skin depth, and skin depth is very related to the amount of s
Ballpark figure for "significant" hole sizes is perimeter >1/2 wavelength, so, at 14 MHz, a 10 m perimeter hole, or about 10 ft in diameter... The hole acts as a dipole antenna (Babinet's theorem say
The mechanism of particle impact charging relies on charged particles (dust, raindrops, snow) touching a conductor and transferring the charge. This is what charges things like airplanes, air powered
Those fans are shaded pole, and should have very low noise (other than the existing 60 Hz noise you've already got everywhere). Brushed motors are the ones that will generate plenty of noise (i.e. v
The UFER ground IS the building ground. You wouldn't generally see a conventional ground stake tied to a UFER ground (if only because the UFER is a better ground.. lots of contact area, low impedance
I've tried a bunch of approaches to shoving wires or small tubes into the ground, including various kinds of knives, power edgers, flat bladed shovels, etc. A lot depends on how deep you want the wir
Good point... for an older house, you would have the usual rod type ground. A house I lived in in the 70's was built in 1970 and had a rod. The house I live in now was built in 1998 and has a ufer gr
Now, all we need is someone to make a trencher that does a 1/2" or 1" wide swath, and then have the rental yards stock it. Too bad that laying sprinkler lines and electrical conduit is a mass market
I laid some wires (not enough) down before I laid the sod on the quasi prepared dirt... Hey, there's a new feature for new housing developers... (you wouldn't want them to think radio.. capitalize on
The VSWR of the 4 square, when adjusted, will depend as much on your feed/phasing network as on the mutual impedances of the elements. When you measured, were the feed lines disconnected at the shack
This stuff is sold as roof flashing.. I don't know that the average Lowe's or Home Depot carries it, but places catering to the roofing trade certainly do. A google for copper flashing will find it.
The usual TV antenna type mast has guy wires (because that 1.5" thinwall tubing just isn't all that strong). I assume though that bringing up the enhanced safety aspect of guy wires isn't appropriate
Depending on why that strap is there, the DC resistance of the material is probably less important than the inductance. The inductance is determined by the shape (low, because it is a large flat ribb
Found on the web (no guarantee of validity, etc.): Regarding my recent query as to whether it is better to weld the rebar cage for a tower base or to tie it together with wire: There were 15 or 20 re
2x2 wood pieces available in 12 ft lengths are also fairly cheap.. They use 2x2 and 2x4 "masts" around here when they need to show where the corners of a proposed building are going to be for plannin
Pete makes great points on resolution... my point was more to show the order of magnitude required...And, these very thin guys aren't really meant to be permanent, just to hold a stand-in up so that
It will work better than it does on your car, but not as well as, say, a dipole. It is, after all, physically short, with a loading coil. The loading coil does have some loss. You're essentially look