Am I oversimplifying?

kb3rij

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Apr 28, 2020
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Suburban Philadelphia PA
I've had my license for about 10 years but pretty much only used VHF/UHF while mobile or on HT -- no HF. Seeing that I'd be stuck at home for a while, I picked up a MFJ1984MP before the stay at home orders. I installed it as a plane end-fed (largely level, 15 AGL at lowest point, will be raising further). Some of the local folks on 10M are using verticals so we have trouble communicating.

I'm using a Kenwood TS-450S with built-in Autotuner as well as a MFJ-986 manual tuner.

1) It looks like I could create a 10M 1/4 wave out of wire easily and hang it from a tree. I know it will require radials. Could I extend it to be 20M 1/4 wave *and* 1/2 wave 10M?
2) Could I hang a 10M 1/4 wave off the antenna stub on the MFJ1984 or would that totally mess up all my SWR?
3) I'm considering trying wiring in my gutter/downspout as an antenna as well...
 

W9BU

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You probably don't want to cascade your tuners. Use the autotuner in the TS-450 or the MFJ manual tuner, but don't use both at the same time.

A friend of mine loaded up his gutter and downspout and made about 100 contacts in a RTTY contest with 5 watts. Sometimes a guy gets lucky with that type of antenna.
 

kb3rij

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Apr 28, 2020
Messages
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Suburban Philadelphia PA
You probably don't want to cascade your tuners. Use the autotuner in the TS-450 or the MFJ manual tuner, but don't use both at the same time.

A friend of mine loaded up his gutter and downspout and made about 100 contacts in a RTTY contest with 5 watts. Sometimes a guy gets lucky with that type of antenna.
I was given the gear by my grandfather shortly before he passed. He won the radio at Dayton but found that it couldn't reliably tune the G5RV he was running so he bought the manual tuner. I've been running the manual tuner in bypass mode most of the time (except for experimenting when I turn off the built in autotuner). The manual tuner supports wire antenna as well.

I'm going to wire up the downspout to see what happens. The worst would be that I waste a bit of time and cut some wire off my roll :)
 

WB9YBM

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May 6, 2019
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Niles, IL
"1) It looks like I could create a 10M 1/4 wave out of wire easily and hang it from a tree. I know it will require radials. Could I extend it to be 20M 1/4 wave *and* 1/2 wave 10M?"

Well, "yes" and "no". "Yes" in the respect that all the standard (i.e. pre-WARC) bands of 160M-10M are harmonically related for the reason that the same radiator can be used for each band. "No" in the respect that antenna impedances change between 1/4 wave, 1/2 wave, 5/8 wave. etc. Back in the tube radio era where radios had to get tuned on a frequency before operating, this wasn't a problem. I've noticed that the modern radios that don't need tuning are a bit fussy and usually need a tuner to match impedances.
 

W5lz

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Feb 28, 2019
Messages
492
Try this, make a 20 meter groundplane vertical. Add a second vertical wire cut for 10 meters. Leave the 20 meter radials alone. And just for grins... That "tri-pole" antenna is simply a two radial groundplane antenna.
 
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