SWR mixture? What gives?

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Cruiseomatic

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I was previously trying to use a 102" for a base antenna until I relised mine was no longer any good and none of the kids at the local "rat shacks" even know what one is let alone identify it so I carefully removed my A99 from the roof to use. Got it all mounted and set ready to go. Checked SWRs and found this:

Am side,
Ch.s 1-15 are 1.5 + but lower than 2. Ch.s 16-40 are 1.5-.

SSB side,
1-17 are 2.0+ but lower than 3 if not barely. 18-36 are 1.6 - 2.0 and 36-40 are1.5 flat.

Tuning rings are froze where they are and it has never done this before and I have never seen this either. Usually if AM were good so would SSB to a point.

What can I try next to risking trying to move the tuning rings and breaking the plastic that holds them? This antenna is already 11 years old and has lines where the fiberglass is looking fuzzy.

Thanks.
 

rescue161

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If it is cracked, there is probably moisture inside the antenna and no amount of tuning is going to fix it.

I would replace it with another A99 or even better, go with an all aluminum antenna, like the Ringo Ranger. The A99 just has a small copper wire running through it.
 

prcguy

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SWR is an antenna system measurement and modulation (AM, FM, SSB) has no bearing on the antenna match. To make the SWR meter measurement stable use a constant carrier like AM and forget using SSB.

Try using some WD-40 or very light oil on the threads of the tuning rings and maybe heat that area with a hair dryer to soften things up a little.

If you cant move the tuning rings the readings you posted with the more accurate AM measurements are not that bad and you will probably never notice any difference in performance by making it 1:1, if that's even possible. Could also be the new surroundings are different and causing some higher meter readings.
prcguy
 

Cruiseomatic

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Could be moisture in it. Will try to loosen the rings when it is not so windy out. Looking into the "Ringo Ranger". Coax isn't 11 years old. It's been replaced. Seems to be working as is though. Made contact with Indiana from Houston this morning on 38 LSB. Just wondering how the SWR readings can be so different when the freqs. are so close.
 
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