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Doesn't need to mention it, the way Maxwell words it explains many things.

First thing, if your antenna is not isolated from the mast with an insulator then I'd cut your feed line into electrical half waves. Thats half wave lengths of what ever frequency you are running. If you have 100 feet of feed cut it into 5 half waves round about 87.5 feet or there abouts minus...

Jesus H Christ:ohmy:

Read Maxwell's reflections. Every antenna out there tries to become a dipole whether we like it or not. The counterpoise is natures way of stealing the missing half of a dipole from the surroundings. Simples:tt2:

The maximum current permissible on R2 and R4 is 60ma. This is the spec for the optocoupler diode on the input side. 1k is suffice on both R2 and R4. The missing diode is between the source leg of the second IRF3205 Mosfet and the input of the primary. This ensures that back EMF cannot spike the...

Actually there is a missing diode on this particular circuit. Plus resisters R2 and R4 have missing values. Any ideas fodendaf? This particular choke is called a Hip Hip Op choke. :laugh:

:oops: lol, wrong picture

antenna choke

Not wearing that one. Dipole sucks.

Hi, you need to tell us a little about your configuration and how you have put it together. For example have you got a SO239 where your coax is fed into via a PLplug, have you got a ground plate where the SO239 is fastened to. How is the copper wire which is your driven element (fed by the...

It indicates where the voltage maxima and minima are in the geography of the antenna, if you cant find where the current maxima and minima are located within the geography of the antenna stick 1.5KW up its ass then go around the antenna with your finger and see which part of the antenna kills...

Too lossy a system. Simple solution is to get some fibreglass the same as the inside diameter near the base of the flagpole, cut the flagpole at 5/8ths or maybe about 6 inches shorter than 5/8ths then insert the fibreglass or delrin so as to isolate it. Leave a good four inch gap. Then just use...

Nice work with the antenna Homer, I'm sure many have learned lots from your input. Top stuff:thumbup:

I'd call that a quarter wave ground plane.

Like others have said, it is not a good idea to remove parts of an antenna that are part of its resonance. It could be done but you would more than likely have to re-tap the tuning coil to make it resonant with the driven element at the same height. However, there may be a chance that you could...

Yep, I guess you are right DB. It just goes to show though, when you get one idiot making elementary mistakes testing antennae it isn't long before you get another following suit. Then you end up with an whole army of them claiming this antenna is better than that antenna when in reality they've...

It probably will be 50 OHM's, you can make any piece of crap display what ever impedance you like, that is not what I'd be worried about. Crap coax = high losses. Lossy coax = pissed off neighbours and shit performance. The braid on the coax is a shield, poor braid means poor shielding means big...

Hi DB, Don't worry, it's not the first time that its been pointed out to these people that using DX is not a good idea for testing antenna's. It has also been pointed out that not using the identical apparatus for each antenna test (same coax, same mounting pole, same rig, same pl plugs etc) is...

All I can say is......huh

I'll just add a little to that about the subjective part. I'm glad the V4000 was mentioned in an earlier post and the phase relationship between the basket and the driven element. I strongly believe after several experiments that there may well be a phase relationship with a half wave element...