Antenna Tuner Woes

Once again I have to decide on if I should use an antenna tuner.

Right now I am using one. A homebuilt Z-match. It tunes 300 ohm twin lead driving an 88 foot drooping dipole (88 feet per leg). Works well on all bands using the tuner. Only running about 500 watts output but the tuner complains at the power level. I hear arcing inside. I know where it is because it arced there before and I am sure it is arcing there now. Makes me wish I did not have to use a tuner.

Why use a tuner. Mainly it provides all-band coverage and filters out harmonics and spurious RF. The only real disadvantage is that it needs to be made of substantial parts to run higher power and it needs to be tuned at each band change. Cost is not a concern because I already have two tuners. A homebrew Z-match good to about 500 watts and an old Johnson good to about 1000 watts.

So why not just use the Johnson Matchbox? Well it does not work well on all bands with the setup I Have. I uise 300ohm twin lead to feed the antenna and it is not kept spaced away from other feedlines like it should be. Works okay witht he Z-match but not so well with the Matchbox.

So fix it. Space it away the way it should be installed. One of these days I might do that but not right now.

Install and use a coax fed antenna that is multiband. The multiple leg fan dipole comes to mind and just a quickly is rejected. Too hard to tune. Takes too much time. It only needs to be tuned once but I have better things to do.

Sepeate antennas for each band. One dipole per band. Can only put up two decent dipoles given the current layout. Okay, one for 80 the other for 40, use the beam for 20,15, and 10.

I used to do that but with a trap dipole. That dipole actually covered all bands but was designed for 80 and 40 using 40 meter traps. Worked well but was a little narrow banded on 80. Only covered half the 75 meter band. That may be all I need to have covered but I know that not being able to go down to 80 CW is going to cause problems. Not that I do a lot of 80 CW work, but I do not want to have to tell myself I can’t.

Whatever we do here, we want to take the tuner out of the picture and cover as many bands and broadly as possible. Looks like we may be considering two trap dipoles at right angles to eachother.

One covers 10 through 40 meters and it is up right now. 10,15,20,and 40. I believe I can add the two 40 meter traps and have this same antenna cover 75 meters too.

Then, take down the 88 foot dipole and replace it with a trap diple covering 12,17, and 30 meters. That would give me coax fed dipoles coveing all the active HF ham bands.

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