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High SWR

View attachment 38232 View attachment 38233 View attachment 38234 View attachment 38235 View attachment 38236 View attachment 38237 View attachment 38238 View attachment 38239 View attachment 38230 View attachment 38231 Ok here are some of the images of the installation I'm not actually done as there are some things I want to change but right now I need to get on to other things like a whole bunch of radios that have been sent in for repairs.


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Any chance we can address the feeding arrangement of the HF antenna in another thread?

Some folks (referring especially to myself) have little to no familiarity with anything other than a basic 3/8 x 24 mounted 1/4 wave antenna.

But...I don’t want to hijack the OPs thread with my questions ;)
 
I tend to think an antenna mount could be well-connected to the body, and still have CMC issues which might cause the SWR to change with coax length.

But, I was just jesting anyway. Lol.
 
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From my experience, take this for what it’s worth cause I’m just here for comic relief and to provoke thought or just provoke depends on who you ask.

Anyway, my experience is make that antenna longer, the SWR reading decreases. Put it back to its original length and do proper grounding, that SWR reading will go down like it did when you made the antenna physically longer. It’s absolutely not the coax, as CK has said thousands of times, there is no magic length of coax.

Sometimes, I’ll get a good pair of insulated pliers and take the end of that whip and drag it around under hood. I’ll cram it and hold it to the positive battery terminal. Then, after the fire department has left, I’ll stand there with my arms crossed just looking at the antenna. I’ll say “well, did you learn anything from all this?” and then just turn and walk away.
 
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I tend to think an antenna mount could be well-connected to the body, and still have CMC issues which might cause the SWR to change with coax length.

But, I was just jesting anyway. Lol.

In that case, I’d ask myself why is that? Is it due to poor quality coax, leaky from center conductor to shield? Does that reading go down with longer length because those CMC’s fizzle out before they reach the meter due to longer coax? Is it caused by an issue with the radio or amplifier maybe? That’s why I like to use an analyzer and my own coax.
 
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In that case, I’d ask myself why is that? Is it due to poor quality coax, leaky from center conductor to shield? Does that reading go down with longer length because those CMC’s fizzle out before they reach the meter due to longer coax? Is it caused by an issue with the radio or amplifier maybe? That’s why I like to use an analyzer and my own coax.

I just put some ferrite on and stopped thinking about it.
 
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I just put some ferrite on and stopped thinking about it.

Not me, I teach it a lesson. My insurance company doesn’t like my approach.

Seriously, yeah I guess you could do that but that’s not exactly fixing the problem. I’ve left my own stuff at 1.7 and 1.8 and ran amps on it, no worries.
 
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Not me, I teach it a lesson. My insurance company doesn’t like my approach.

Seriously, yeah I guess you could do that but that’s not exactly fixing the problem. I’ve left my own stuff at 1.7 and 1.8 and ran amps on it, no worries.

I don’t run anything hard enough for 1.7, or even 2.0 to be an issue.

I did not always believe it to be the case, but I now think a setup, well bonded to a vehicles body, with good coax, and with a properly functioning amplifier and transceiver, can have common mode issues.

That said, my end game isn’t understanding holes and electrons, but operating my radio. Flip the same coin over; when there’s room for improvement to the end game I’m all in.
 

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