measuring SWR with it like this has worked well. The problem I ran into was there was a noticeable difference between when the tailgate is up or down. i originally had it the way you said it (in my first confusing post, just before the pics).

I'll switch it back around tomorrow morning just before our trip. That's all I can do at this point. there is a practical limit to the precise lenght of the coax (I can't have it shorter than the run). 18' is ideal, but may not be possible. This is another battle for me to fight. My goal was to find the problem, fix it, and have this thing, at the very least, working by tomorrow. We did it. I appreciate all your help. I obviously have some more work ahead of me for this thing.

 

Forget what the SWR meter is telling you. It is irrelevant until you stop shorting out the antenna connector. You are cooking your radio right now. You have the plastic insulator on the wrong side and are directly shorting the center conductor to ground. You need to do like I said and put the insulator on the top.

Then and only then can you start worrying about SWR. It is normal for the tailgate to effect SWR when it is setup properly. Anything that alters the ground plane is going to alter the SWR a little bit.

 

If you are running RG58 18' is fine. its RG8x Mini that is 14.25. Others will argue length but improper length on HF you will never know if your radio is tuned, The best way that I have done, is have the radio setup outside of the truck run an 18ft jumper to the antenna so you dont run back and forth. Then run your coax.

Also are you running the wilson 4ft that is like a firstik?

My setup.

 

Please note, the plastic insulator is in the CORRECT place on this one!

 

I also prefer the silver PL connectors,

 

no, I switched the antenna over once you told me... you had me scared . I do have it set up properly according to those pics now, and it was decent (until Outdoorsman broke his antenna). I'll keep working with it some more, but not right away. This month is getting expensive...

 

IF you can snap some shots of yourset up..

 

being Easter weekend...I'm busy as all get out -- and our trip on Friday obviously took longer than expected, lol. I'll post some pics up soon.

 

a 1.1? you mean a 1:1 or 1.1:1?? lol


Oh boy....

Your 102" whip with the 6" extension = a full 1/4 wave. CB retards with old wives tales say only use 18' of coax for the same full 1/4 wave effect.

I've got a radio setup pushing 1kw on a bird43 meter(the only meter to measure true rms) that will bleed over your car stereo audio from a couple hundred feet away in my rig. I've got a 6' line of coax from the antenna to the meter, 3' jumper from the meter to the pill box, 3' jumper from the pill box to my radio. 12' overall and my swr's are a flat 1:1 on radio power and amp power. You want the shortest lengths possible, excess coax = RF choke. I am sort of old fashioned using nothing but 3' increments but the 18 and 14.25 length crap is a myth.

If you're getting different swr readings with different lengths of coax you either suffer from RF choke(due to coiled up or excess length) or are using an swr meter that isn't even worthy of being a wheel chock. PERIOD.

You gotta watch going to radio shops as well(truck stops in particular!). Half these hacks read about adding a resistor and diode, volting finals, and changing led colors and think they can run a radio shop. Get your antenna mount corrected, tune the antenna, make sure the antenna has a good ground as well as the radio, and you should be in business bro. FWIW, It took me about two hours to get my antenna from a 1.5:1 swr to a 1:1. If you're running a regular cb setup(even "a peaked and tuned" radio)anything under 1.5:1 is sufficient. The lower your swr is, the lower power loss you'll have which=more transmit power.

 

I've tried to explain this to no avail for years. I install radios on emergency vehicles all the time and we sure don't use 18ft.

 

Say what you will, I dont care at this point, Myth or not, I know what has worked for me, What has worked for others, What works for many out there,

Better call Wilson, Firestik and other companies selling 18' coax lenghs.

Dont know what to say other that this is what has worked for me in my truck and thats all I came here to share was what worked if you feel the need to call it BS go ahead.

I have read about velocity factors and its how I came to 14.25ft with my coax and it worked, It droped the match...

Dont like my 102" whip with a 6" Spacer oh well it works for me as well and have had no problems with it.

Call it a 1.1 1:1.1 or a 1:1. Obvously you know what I was saying so if you feel the need to correct it and it makes you feel better, Go Ahead.

 

Wow dude, I was simply correcting you. SWR=Standing Wave Ratio 1:1 ( One to One or flat ratio)....get it?? That's simple algebra.

A 102" whip is the best antenna out there, show me where I put down using a 102. I have one on my truck with the 6" spring there dingbat

Oh yeah, wilson and other companies make 3' increments of coax all the way up to 18'. Just because the hack shop you go to doesn't stock it doesn't mean that it isn't made.

The ONLY time coax length matters is when co-phasing an antenna. If the antenna's aren't at least 8' away you're wasting your time anyhow because sometime you can actually hurt the radiation pattern having co-phased antenna's too close together.

I don't claim to know alot about alot of things but after installing radios in the fire dept.'s rigs, my pickups, my rig(which has almost $1500 in equipment), and having a HAM Tech for a dad.....I kinda got a handle on this 2 way communication thing.

Cool your jets bro, don't take my education/advise as an insult.

 

I have read pros cons and ups and downs on coax length, There is a thing called velocity factor. All coax have it. ON HF such as cb for some reason it tends to effect it more. In most cases if you do not run the required lenth or x2 it will effect what your SWR reads.

Most police and fire use VHF and UHF "exc hwy patroll most are between 30 and 50mhz" and the velocity factor does not seam to effect it vhf or uhf. IF your dad has a ham tech lice ask him if he has an ARRL Handbook and if it talks about velocity factors and coax lenths, It does not dismis this as a myth.

Sorry for taking strong defence, I just know what I have read. I have sat out in my truck for 3 hours messing around trying different things, I have messed with cb's since I was 14. I have built many antennas for hf vhf and uhf

the average joe spends an about 49-120$ for there radio and they use the built in SWR meter and dont care to spend big bucks on more equipment. So I sudgested something that would help him get a proper reading on his equipment and work from there, IF your reading a wrong SWR from the getgo you can adjust your antenna all day with no results.

The true and best way to read your swr for an antenna before even hooking up would to your rig would be an SWR analyzer.

 

Thats funny you mentioned Apollo Communications. I got my setup from them. Good guys and down to earth. I run a Cobra 25 NW peaked and tuned with a wilson 5000 on the center of my roof.

 

Damn man, a wilson 1000 can handle up to 1000w rms on a bird43(2500 pep/garbage watts). That's overkill for a 25 lol

 

Maybe/maybe not. For a few bucks more you get a better antenna. Never know what I'll do in the future and I like the best antennas I can get.

 

I got ya, the transmit and recieve is the same, it's just able to handle more power.

If you're running more than 1k rms you better have 4-8 deep cycle batteries and 2 high output alternators or a motor maul at the very least....lmao