wolfwings

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I... thought my SWR meter was broken at first. I was getting a 1.3 SWR with the naked antenna no matter what I did.

Then I hooked up the AM/FM/CB splitter, and re-tested. THAT let me throw the SWR all the way over to 3.0, so at least I know the meter works. But I ended up being able to get a 1.1 SWR on channels 1 and 40 equally, and it actually dipped lower (though I couldn't measure accurately below 1.1) towards the middle-channels. I think I can safely go buy a smaller antenna. =O.o=

And the 'quick fold over' is worthless. I'm going to delete it, and put the potbelly spring in with a shorter antenna I think, rush home, take a shower, then head to work. Ah well, anyone out there want a screwed-in-once 102" stainless-steel whip antenna in the KCMO area? Free?

And just to prove I did it:

Flat | Top-Level Comments Only

From:

lionman.livejournal.com

So, let me make sure I have this right: Your antenna is longer than your car?

From:

wolfwings.livejournal.com

The antenna, layed down flat, doesn't reach over the front bumper. And it's about 18 inches forward of the rear bumper to the point it's mounted at. =^.^=

It DOES reach end end of the lower end of the windshield and lay down quietly there though if I use the quick fold-down.

From:

texxgadget

Several things...

1.1 to 1 is about the best that you can get in real life, with
1 to 1 being perfect but impossible to attain.

Before you scrap the 102", Ive a few questions...
Was it vertical when you tested it and what was within 102" of it when you tested it ?
If you really want to dump it, let me know, Ill take it.

1.1 to 1 on the edges of the band and closer to 1 to 1 in the middle is
like nirvana. I cant see you getting that on a shorter antenna and worse
on the 102".

102" is about 1/4 wavelength for CB wich is what you should have along with a good ground.

Its possible to get a good SWR with a lossy antenna.
The question is whether are you getting a better reading because the
antenna is perfectly tuned or whether resistive loss is making it look like
a better match. I cant see a short antenna holding that good over a 1.5
mhz range.

What we really need to do is get in there with a reflected watt meter which
is different from an SWR meter.

Lets take this conv to email and dig into it better.
Something sounds screwy to me.

Frequency of an antenna is tuned by length.
Theoretically an antenna can be tuned to only 1 freq but antennas can be
made resonant over a wider range by increasing the diameter of the antenna.

A 102" section of 6"dia copper pipe makes an AWSOME base antenna.

Again grounding and pseudo grounding will make of break you.

Email me !

From:

wolfwings.livejournal.com

The antenna was as vertical as it gets, and the photo there shows exactly where I tested it with the SWR meter, the closest things were the power lines about 60 feet north, and the house 30 feet in front of the antenna.

And yeah, this antenna is nirvana for reception, but I'm worried about the stress on the roof even with the 2.5" flat-disc spreader mount holding it up. Initially I was thinking my meter was broken because the readings were SO good, with no fiddling at my end, that until I got all the adjustable bits in place (naked antenna first, then each piece hooked on and re-tuned in turn before adding the next component) I couldn't shift the SWF up or down from 1.3 at the edges.

I was more thinking of getting a shorter antenna for day-to-day use, and either use that full-time or just clip the 102" on for long road trips. I know the reception will be worse, likely MUCH worse, but I used the 102" initially since it's dirt-cheap AND I was worried about getting good enough reception at all since I wasn't sure I had enough roof for a ground-plane or not. Right now though I can clearly hear, and be heard by, trucks at the truck stop about 6 miles away from my house. That's better than some base-stations. :-)

From:

uplinktruck.livejournal.com

You are right to be worried about the roof stress. Sheet metal was never meant to support something with that much leverage in the wind.

From:

wolfwings.livejournal.com

Yeah, exactly. It's sheet metal on a curve so it has a lot more rigidity than it might otherwise, but I'll switch it to a shorter antenna until I get my cell-phone booster kit, then I'll re-purpose the 'stock' antenna mount position for that, and likely re-mount the CB antenna to a mount I'll fabricate off either (or possibly both) ends of the rear bumper, which'll also drop the antenna about 4 feet in the process.