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Antenna to cover 3.843.00 - 3.898.00 - 3.913.00

Tony - a built-in tuner, or an external autotuner, might not be able to cope with the SWR of something like the G5RV at some frequencies, especially the lower ones you're specifically asking about.

Say your antenna is adjusted for best performance at 3890 KHz and you want to operate at 3975, for an example. That's 85 KHz difference. With a good manual tuner it would be no problem, but it might give an autotuner a headache.

On higher frequency bands, like 20 meters, an antenna cut for the middle of the band (14.200 MHz) will cover the full band (14.000 to 14.350) without complaint from most built-in tuners because that 350 KHz is much less of a percentage at 14 MHz than the 85 KHz in the earlier example is a percentage of 3.5 MHz.

Lower frequency = longer antenna, with narrower bandwidth.
 
Any easy one to make if you need to use coax is the fan or "multi-band" dipole.

http://www.hamuniverse.com/multidipole.html

There are a number of ways to space the wires. You can do it like a maypole, or just run them all in the same direction with spacers made from pvc or somthing. BTW, while I wouldn't necessarily recommend buying a wire antenna (they're just too easy and cheap to make yourself), I will make one exception, and that is if you have a space problem. The Alpha-Delta DX-CC is a fan dipole, except that it uses loading coils on the ends of the 40m segment to get you 80m. They charge too much for the antenna, but it does save you a lot of headache if you have a small lot or can only get the mast up to a certain height. BTW, you can run these inverted v or flat, whatever your flavor is.
 
One last comment about antennas and I'll leave it alone.

When you get a chance, take a look at a few of what other people are using for the HF bands. I think you'll find that most are using some sort of 'basic'/un-fancy antenna, and until you get to around 20 meters or so, most are sort of horizontal rather than vertical. Not that horizontal antennas are all that much 'better', but because in general they are just easier to get into the air. 'Bending' them is allowed, just don't bend them back on themselves, sort of.

Height means something. Most people can sort of get an antenna for 40 meters to a 1/4 wave above ground (30 feet, give or take a few), which is good. Good luck with anything below 40 meters :), still would be nice, but not quite as easy to do.

Verticals for HF are sort of large, and do require something to 'work against', as in a ground or groundplane of some kind. Plain old dirt does work. Making that dirt more conductive, putting radials in it, makes it work better. Don't bother about sprinkling metal shavings, that sort of thingy, in the yard for better conductivity. No real 'help' till you can connect all them shavings together. If I can figure a cheap way of copper plating my yard, I'll do it! Copper turns green so who'd ever know anyway, right? Those radials only have to be deep enough so they don't get caught in the lawn mower. Ground rods work for electrical grounding, but not too well for RF stuff.

The thingy about radials is that using something like a metal water line does work. But the other end of it can also be straight into a neighbor's house. Not so good sometimes. Same for fences.

Half the fun of it is getting there, so enjoy it!
- 'Doc
 

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  • @ BJ radionut:
    EVAN/Crawdad :love: ...runna pile-up on 6m SSB(y) W4AXW in the air
    +1
  • @ Crawdad:
    One of the few times my tiny station gets heard on 6m!:D
  • @ Galanary:
    anyone out here familiar with the Icom IC-7300 mods
  • @ Crawdad:
    7300 very nice radio, what's to hack?