I'd bet that in most cases, the outside of the shield (if not buried) is a lower impedance (unless it's just the right length) than anything in the soil, though. "This one bothers me. Remember that
Well, some of it does reradiate from subsurface (hence sounders and other "radars"). And in things like a Beverage, the currents in the dielectric under the wire form an essential part of the anten
<big snip> The late Henry Ott taught in his EMC workshops that above a few kHz, the impedance of a conductor with even a very large cross sectional area is dominate by inductance. yes - the inducta
The Starlink emissions are regular old spurious EMI from digital circuitry. Odd as it may seem, spacecraft have no requirements for unintended emissions. That is, there's no Part 15 or CISPR type ru
Youre talking about the round DIN connectors here (like used for MIDI), versus the RF DIN connectors? Yes, DIN and mini-DIN are way too delicate for stage use.. you want something you can step on or
yeah, these guys are actually stealing wire out of live streetlight circuits. And of course, they don't realize that optical cables have no copper, so there have been cases of them cutting phone c
As noted in another email, radials buried, on, or near the ground are likely not identical, (different soil properties if nothing else, but also other stuff near by, unless youre out in flat farmla
Have to issue a correction here. The ground system is part of the antenna. It has to be connected to the unbalanced feedline at the feed point in order for return current to travel on the inside sh
At some point, isn't that basically making a Beverage? "Anyway, in some cases they ran stupid long radials but in very limited directions (like a gob of them over just 5 degrees then 10 degrees etc e
If it's a perfect conducting screen and of infinite extent... It doesn't matter. If it's a grid of some sort - then it's sort of "soil with increased conductivity" from a "interacting with the fie
True, but I wonder how long the vinyl will last - there will inevitably be pinholes in the coating. Granted, *any conductor* in the soil will improve the performance, even if half rusted away. All
20-25% is actually what Fair-rite gives as a tolerance for their cores (at least for the EMI suppression family) - Chip beads are 25% So if you've measured 20% variation, that's probably within spec.
yeah - the book by Snelling discusses all the variables. The Fair-rite catalog also goes into the mfr process. There's a reminder at the bottom of most of the pages that says "if you need better, c
Probably because it is http:// not https:// Bitdefender warns me that Rudy's website is suspicious and blocked access to it :( 73 Mirko, S57AD V V pet., 14. nov. 2025 ob 20:23 je oseba Phil G via Tow
most fan dipoles (e.g. DX-CC from alpha delta, if you want a commercial unit) use the same element for 40 and 80 with a sort of trap. And if you did have a 40/80 fan dipole, the two elements would
"sort of trap" - I wasn't sure, because modeling it as a straight inductor didn't seem to produce feedpoint Z that matched the measured values. So I just assumed it's sort of a L with parallel C, bu
Sure, that probably reduces the C by a factor of 2, so coupling is 6 dB worse. Still not particularly well isolated. 16 MHz seems about what it would be for L and parasitic C - It's been a long tim
The DX-CC is exactly what you describe - three wires connected to a single feed point, spaced about 6-8" apart. An element for 10, 20, and 40 (15 is third harmonic) and 80 with loading coils on the 4