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Lug connections and very high SWR.

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Mentor3006
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Lug connections and very high SWR.

#411169

Post by Mentor3006 »

Obviously no key up just using auto SWR right now, but I set up my Firestik II using the van hood channel mount, which came with a lug style stud. I have never set up a lug connection and there was zero documentation on it..

I put the ring from the center conductor between the lock washer and flat washer on the bolt in the lug connection, then rubber washer, mount, rubber washer stud etc... The ground ring was bolted the the stainless steel mount in the provided hole. The antenna mount is sloppy loose though, like the bolt is too long and my SWRs are way high, like 7 on channel 40 and 4.6 on channel 1. Needless to say I powered it off and am digging for answers.

Could this be because of the sloppy in the mount? Should I add another washer? Ground problem maybe?
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Windwalker
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Re: Lug connections and very high SWR.

#411170

Post by Windwalker »

Its always good to have xtra grounds and all connections have to be tight.
My opinion is that Firesticks are a bit difficult to tune for swr. Their reputation is also poor but they do have a snappy name.
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Mentor3006
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Re: Lug connections and very high SWR.

#411171

Post by Mentor3006 »

Well, given the use case, I figured Firestik was the best way to go, however this seems WAY off for even that. I think I will run an added ground lead from the mount to the frame and see what happens.
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Mentor3006
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Re: Lug connections and very high SWR.

#411190

Post by Mentor3006 »

So coax got swapped with a Firestik FireRing type. Moved the channel mount to the front bolt on the fender to allow more distance to the top part of the van.

I was able to get SWRs to 1.2 on channel 1 and 40 UNTIL I put the cap on the tunable tip...

Then they shot up to 7!

So it looks like the tunable tip itself is shorting out.

I have a 12ga ground lead running from the fender bolt / antenna mount to the chassis ground.

So I eliminated all issues short of the antenna itself, and yeah, looks like a defective antenna. Going back for warranty replacement...
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Mentor3006
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Re: Lug connections and very high SWR.

#411212

Post by Mentor3006 »

So per recommendation here I snagged a new SWR meter, and a jumper to insure everything is minty fresh.

Got the same readings on the old Firestik, tossed the replacement on, and fiddled with the tunable tip some until I just barely have it above being bottomed out. 1.3 on channel 1, and 1.5 on channel 40. I suspect if I drive out of the neighborhood away from all the trees those numbers will eke down just a point or so. Considering I am mounted on the very front of the drivers side fender, I guess that will have to be as good as it gets.

The first Firestik is already in the Amazon box, looking for tape and will ship it back tomorrow when the UPS store opens.
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Mentor3006
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Re: Lug connections and very high SWR.

#411216

Post by Mentor3006 »

So after extensive tuning I got it to 1.3 on channel 1, 1.4 on channel 40 and 1.1 on channel 20. I'm done messing with it. Oh and I have a Red Firestik II and the cap went AWOL on the first one so I got red caps, looks good against my red van...
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Mentor3006
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Re: Lug connections and very high SWR.

#411229

Post by Mentor3006 »

So a quick update, the Astatic 302-PDC2 SWR meter I ordered off of Amazon [Please login or register to view this link] went back today. It was a complete waste of plastic and metal. Simply put I couldn't get the same result between 2 tests in a row. And the needles wouldn't zero. I ended up using my RadioShack meter, and I realize there are multiplemodels, mine is the 21-534, and my friends MFJ meter,

I am not 100% certain of the model but it looked like the MFJ-872... [Please login or register to view this link] and both of those meters agreed. Auto SWR on the radio was close to the readings of the meters until it wasn't, then it was, so not super reliable it looks like...

MODBREAK_HEADBozo

combined posts
So I am going to tidy this thread up and summarize what I did...

The ring lug setup was junk yes, but that wasn't the actual problem. The issue was an internally shorted Firestik that is now back in the possession of Amazon.

I installed the replacement and got reasonable SWR and probably should have left it alone, but Windwalker 1 talked me into swapping in one of my old 102s. Which brought the SWR down even further, but was still reading like the antenna was a smidge long, then swapped in a 102 that I had popped the ball tip off of and the SWRs came in as close to perfect as I think is possible, on AutoSWR in the radio, in my RadioShack meter and in my friends MFJ meter.

Did I meter it out with a $300.00 Dosy meter? Nope, not gonna either. Don't have access to borrow one, and too cheap to buy one when I have other projects that need money.

So long story short, the ring lug cable was fine, it was the lug mount itself was fertilizer. Just would NOT lock down to the mount. Bad Firestik, pretty good Firestik, really good 102, fabulous 102, done.
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