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Sorry Marconi, I wasn't giving you any credit for what you said by what I said. What I said is just a simple fact. As for those antenna modeling programs, I've played with them for years. They can certainly be enlightening, but they are far from infallible (the author will tell you that)...

That 9 and 18 feet thingy is a VERY rough estimate, not close really. You have to factor in the velocity factor for coax if you want an electrical 1/4 or 1/2 wave length. That velocity factor changes for the different 'types'/'sizes' of coax, they are not all the same. If you use an SWR meter...

They are both 1/2 wave length antennas so should have the same performance. Biggest difference would be if that dipole is horizontally polarized/mounted. Otherwise, no huge difference either way. - 'Doc

To the best of my knowledge, my yard and a metal concert have nothing in common. And so that schlub can stay out of it. - 'Doc

If the antenna is bolted to the metal tool box, the tool box to the bed, then all you'd really need is to make sure the bed is 'bolted' to the frame of the truck (makes good electrical connection). There's no need for a separate ground wire from antenna mount to the frame. Think about it... -...

Just for grins, would anyone be interested in operating an 'IRLP' node? All you'd need would be a radio and authorization. A friend has a node (computer etc.) for sale. - 'Doc

The larger number of turns in the coil the lower the frequency. The smaller number of turns the higher the frequency. Try the smaller coil on 20 meters and see what happens. Without some test equipment, how else can you find out? - 'Doc

An end fed 1/2 wave antenna will perform just like a center fed 1/2 wave antenna, the only difference is in how it's fed. An end fed antenna can be more convenient in some circumstances. Because of the very high impedance when it's end fed, there's some losses associated with it, not much, but...

Evidently he's enjoying himself! That's good. Other wise, that dweeb better stay out'a my yard... - 'doc

No matter what the length, all of those end fed wires are more or less a compromise. They all require a very good ground system to 'work against'. Sometimes that 'ground system', counterpoise, whatever, is the feed line feeding the thing, but the 'other half' is always there. They are...

That 40 meters frequency is only a guess, can't remember exactly what the freq was. I've done SSTV for a lot of years, mostly on 20 meters. It may not always be hear-able but there's always somebody there. Everybody is just waiting to hear something, so send a picture and you'll get a reply...

I've had a 'Walt Williams' power supply for a little over 35 years, yesterday it died. You'd have to have had one to understand, it's been a work horse. It's a 70 amp power supply (at least!), and hasn't been turned off for more than a week in that 35 years. I told him I wanted a 70 amp...

You might try 7.136(?) and 14.230, there's almost always someone on 20 m. And the digital stuff on 14.233... - 'Doc

You had to go back five years to complain about spelling? Bet you could find a lot of it without having to go that far back... - 'Doc

How deep? Deep enough so that lawn mower doesn't 'catch' on it. Deeper isn't all that beneficial, but whatever is convenient. - 'Doc

Yes you can, or at least parts of one. I wouldn't paint an insulator, but other than that, cover all of it. Doesn't matter if the paint is conductive or not, except for those insulators. Will that painting affect what you hear? I seriously doubt it, but you might stay away from blue, gives...

Now read that post again. This isn't about a 102" whip, but a loaded antenna. - 'Doc On second thought, it would apply to any antenna, loaded or not. If you add length to a 'tuned' antenna then you can expect it not to be 'tuned' any more, you changed it's length. It has nothing to do with...

Read post #73. - 'Doc

Think of it this way. You usually 'tune' a mobile antenna by adjusting it's length. So, if you change that antenna's length by adding a spring to it, you just 'un-tuned' that antenna (if it was 'tuned' before adding that spring). If you add some then you have to remove some to stay 'tuned'...

You are aware that the center conductor is copper coated aluminum? - 'Doc