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It does affect resonance, my simple model from this afternoon, 1/4WL CB antenna over a decent groundplane: R30.93 j2.177 with short receive antenna installed R30.96 j2.173 without short receive antenna Like I said, such an insignificant amount it would be impossible to see any difference...

An insignificant amount of interaction, I thought I'd model it just to see how much interaction, hardly visible is the conclusion. Whenever we put any metal object in the near field of an antenna there is the possibility of mutual inductance, especially if the metal is in the same polarisation...

How are your home construction skills? a Moxon rectangle is quite easy to build, excellent F/B ratio, similar forward gain to a conventional 2 element beam, 50 ohm feedpoint impedence, and a much reduced turning circle, think win win ;) Moxon Antenna Project

Believe it or not, the smaller resonator and the narrower bandwidth is more efficient than the larger resonator, the increased bandwidth is as a result of loss, the metal cap of the larger resonator adds capacitance to the inductor, that's a bad thing.

At MW frequencies there is little danger due to RF exposure, even when very close to the antenna, at 500KHz and 10KW, the high limit area is very close, approximately 6 feet, check out the following calculator: Radio frequency power density calculator The controlled limit applies to...

I use neither, but here's a piece from W4RNL you may find of use: My top 5 backyard multiband wire HF antennas

I use the 4 element version on 10m, I reduced all elements by around 4" and left the spacing as original, although these are easy enough to adjust the boom is a little too short to benefit from a change in element spacing ;)

Dipole counterpoise wires? What a crock of ---- :whistle:

Ground absorption is a killer at 27MHz, which is one of the reasons why a ground mounted vertical is a bad idea, that and the fact any terrain irregularities, including buildings, is going to kill the signal off pretty quick, certainly for local communication, height is indeed might. I remember...

You can use your tuner with most antennas I'd venture, so no reason why not with the hamsticks, however I'd look to borrow someone's analyser and make sure you get the antenna resonant first. The 10m hamstick is pretty much a 1/4WL antenna and will work very well indeed, the more loading you add...

Marconi, Cody was talking about efficiency, a full 1/4WL antenna can be near 100% efficient, that is, 100W into the antenna is 100W radiated from the antenna, no heating due to loading, a shortened vertical is less efficient, if we continue to reduce the antenna length, and increase the loading...

Portable antennas? I have a coupe purchased antennas, one is the buddipole, and whilst it can feel a little feeble I'm more than happy with it's performance, at least it's based on good solid concepts rather than trying to convince me it's the greatest antenna the World has ever known with low...

Yes it can be undone, but you'll need to reconfigure the solder pads back to their original configuration, it's for that reason alone I don't remove anything from the board, merely lift one end of a component, be that a resistor or diode, of course a soldered jumper is easy enough to desolder. I...

If you have a good clean installation then the chances are your hamstick will have a low feedpoint impedance, this is why you have to add shunt inductance to the base of the antenna in order to match it to 50ohm. With a shortened antenna you have to tune the antenna for resonance, and then tune...

My comments were in response to Cody's understanding that a vertical antenna has to be at least 1/2WL high to be efficient, that isn't the case, there are situations where a ground mounted vertical can have a near 100% performance and very low take off angle, but this has everything to do the...

It's a short, inductive and capacitive loaded, dipole by the looks of it, I doubt it's radiation pattern is much different from any other ground mounted vertical antenna, I think it is expensive for what it is, I'm always concerned when an antenna manufacturer specifies a length of coax that is...

That all depends on what you understand by the term efficient, a ground mounted vertical antenna can be almost 100% efficient, the effect of Earth doesn't disappear at height and it isn't necessarily the ground / dirt below the antenna that enhances efficiency, it may well be the dirt hundreds...

Cody My main interest is amateur radio, although I still use a CB radio at home for chatting with a couple of local friends, so my experience with some of the CB antennas is limited, especially the Wilson range, but I think I know the antenna you are talking about. When we add an inductor...

On the mobile theme, and sorry for the thread creep, a coil at the base of an antenna requires less inductance than one in the centre of the antenna, why? because there is greater capacitive loss in the coil at the base of the antenna than there is in the centre, it reduces coil Q, and for...

He is discussing the earth losses of a mobile installation and goes on to explain ways of minimising this, the latter would sidetrack the thread somewhat, however, I'll do my best to explain. This is an inductively shortened HF antenna, by that I mean it has a coil somewhere along it's...