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Discussion Starter #1
I am having an issue with adjustments and would like advise.

I have a 3" adjustable firestik with bandi mount setup. I was having big problems grounding everything so today took it apart and ran a ground wire. After I was able to get SWR readings at about 1.7 on channel 1 and about 1.4 on channel 40. Finally!!!!! Acceptable readings. So, I put the plastic cap back on the antenna. When I check out the swr readings now, Channel 1 - 1.5; Channel 40 - 3.5. If I take the plastic tip cover off, the readings return to within range.

Why is the plastic tip cover causing this? How do I remedy it?
 

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you take readings with the cap on.

however you plan on using the antenna (cap on or off) is how you want to adjust the SWR.
 

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Discussion Starter #3
I plan on using it with the cap on. Just think it is very odd that I get great readings with the cap off but horrible with it on.

Does this mean I need to adjust it, put the cap on, then take my reading?
 

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Make sure you close all the doors when you take your readings too.
 

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It is a PITA but that's how it has to be done. But look at the bright side.....do it once and you're done.
 

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Discussion Starter #8
Make sure you close all the doors when you take your readings too.

That affects the readings? I was getting in and shutting the doors every time, but with outside temps of 101 decided to just leave the door open. Ran up the ladder, adjust, then check the meter. Repeated until dialed in. Or thought it was dialed in. lol
 

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if you plan on driving with your doors open then you will be ok. :jester:

set up as if you were moving. every little thing can affect performance of your transmission.
 

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I've noticed with a rear door hinge mount, the antenna tends to look electrically short. You can probably run the adjusting screw just about all the way out and start from there. You'll probably be pretty close.
 

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Discussion Starter #12
I've noticed with a rear door hinge mount, the antenna tends to look electrically short. You can probably run the adjusting screw just about all the way out and start from there. You'll probably be pretty close.
I agree with you, or at least I did. LOL That is about were it is, almost all the way out, but with channel 40 being so high I am going to go down I guess and see if that lowers the swr.

Have to wait until the morning, but I am about to run out and take a quick reading with doors closed. I am curious at the difference.
 

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I had to adjust mine almost all the way out which meant the rubber cap didn't have as much to grip. Then when I went through an underground parking lot the antennae banged and rubbed. Later on I noticed the rubber cap was missing along with the adjusting screw. Ended up replacing the whole antennae. Would have saved myself some money by removing the antennae before entering a low ceiling area.
 

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Discussion Starter #14
Got it in this morning. Blows my mind at the difference of having the cap on and having it off. Yesterday, with the cap off, I had to adjust the screw almost all the way out. With the cap on this morning, I had to adjust it almost all the way down. At least I don't have to do that again.

Oh and thanks to all for the help! Got to love this forum!!!!
 

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I've noticed with a rear door hinge mount, the antenna tends to look electrically short.
Because there is not enough ground plane there for that particular antenna.

Try a Firestik Firefly or a Wilson Flex, both of which do not need much if any ground plane to tune up.
 

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Discussion Starter #16
Because there is not enough ground plane there for that particular antenna.

Try a Firestik Firefly or a Wilson Flex, both of which do not need much if any ground plane to tune up.
I looked up the one I bought after seeing your post. I have the FireStik FL3-B Three Foot FireFly Antenna With Tuneable Tip, Firestik K4 stud mount, k1-a quick disconnect, and the K-8R18 18' Fire-Flex coax cable with Fire-Ring. Hopefully this is a good setup.
 

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I have a 4' Wilson flex and it had to be adjusted about as long as possible. I don't have a quick disconnect on it though. I think that adds to the length of the antenna so that may be why yours needed to be adjusted shorter.
 

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Discussion Starter #18
I have a 4' Wilson flex and it had to be adjusted about as long as possible. I don't have a quick disconnect on it though. I think that adds to the length of the antenna so that may be why yours needed to be adjusted shorter.
Yea the quick connect adds about 3" or so to the length. I also have the spring which is another 3-4". Learned the hard way about not having the spring on it. LOL I use the quick connect because I cannot park in my garage with the antenna on and it makes it easier for those times I need to remove it like if a hail storm comes through.
 

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I tuned my antenna yesterday. When I did my reading I had 1.5 on ch 1 and about 1.8 on ch 40. When I went to ch 19 it barely registered.

I like the quick disconnect, very handy.
 

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I tuned my antenna yesterday. When I did my reading I had 1.5 on ch 1 and about 1.8 on ch 40. When I went to ch 19 it barely registered.
Make sure you're reading the right scale on the meter; by definition SWR cannot be lower than 1.0.
 
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