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High SWR

Getting rid of the quick disconnect and going to a solid stud. The mount I have now has a poor 2 piece insulation. Ohmed mount and if it’s to tight it showed 9.990 ohms in the 20k scale. Loosen mount short goes away. Antenna to truck 9.90 ohms. So there is a short.
 
9/100ths of an ohm on the 20k scale? I’m not sure what you’re showing with those values.

Is this from the braid side of the mount, or the antenna...in other words, are you saying you have continuity from the actual antenna to the truck body?
 
I am currently in the designed mode for my F-150 this is a new truck and I'm designing a bed mount for the antenna. I will post some images of the installation and of the results of the antenna matching issues as time passes I will be working on it today so I may have some images ready today. I have experienced some issues with the match on the older mounts but not really thinking the mount is the issue as I'm just try ing to come up with a more substantial or more solid mount. I will try to get some images of this mount it will not suit everyone because it is mounted on the tie-down points but still lets the locking tie-down in place.
 
After digging and doing more research. Coax cable that I have is too long in length. The other coax cable that I used was too short. I found the formula to correctly measure length of coax which takes into account the velocity factor. I have 30 feet of LMR 400 and the new cable that was ordered will be 9 feet shorter. I am running a 2:1 swr Because that cable is a full wavelength with a quarter wave antenna. The new stud mount will be here Friday and we will see what happens after I put it all back together. Everything else checks out owned metered tested this is the only variable that I can think of

I have used many different lengths of coax jumpers & runs directly to an antenna & I have never measured any of them & had ZERO issues with the SWR.If changing the coax length is changing the SWR then you have another issue that you are masking with the coax length.In 55 years of radio it has NEVER been an issue here so how can that be when I never measure any coax & I have had ZERO issues? It's been debated for years but I have never seen any PROOF that it is the reason anyone has a High SWR reading. Coax Length is a MYTH from a long way back.


SIX-SHOOTER
 
As mentioned coax length doesn't matter. Coax connections are usually the problem or it's been bent/crunched someplace.

If you're mounting in the bed of a truck you will often need grounding to frame. I've mounted in beds of trucks many times and grounding to frame always helped.

If you know coax and antenna isn't the issue than pictures of your mount and location would be very helpful at this point.
 
Also, the bible of Mobile Amateur Radio Installation is:

www.K0BG.com

Deals with every aspect.

My first post in your thread mirrors my use of this resource: be willing to keep untying the knot by mentally starting over.

Going over one’s install via his categories is the lowest-effort approach (believe it or not). Each category heading is a potential start over point (is how to approach it).

— The categories refer to each other, as each has a bearing on the other. One can go in circles.

There’s a beginning and an ending. End of Phase One (where you are) is that the equipment is installed and nothing’s blown up or caught fire.

Phase Two is verifying componentry is correctly installed, and (indeed) something or several somethings is off.

— RF BOND
— ANTENNA GROUND
are what I’d suspect from this distance.

Thus,

ANTENNA MOUNT

is where I’d open that mighty tome and make notes during the second reading. One might wander around with links the first go-thru, but go back to the DIRECT wording of this section.

Maybe it’s the most important section.

.
 
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Bed is steel. I agree. I’m not in a rush I want it done right. Not half assed. I have gained patience. Worked outside in the Texas heat for 12 hours so I’m not touching it today. Yes I will get some pics tomorrow. Mount arrives tomorrow. Canceled coax order. Coax tested good.

REALLY APPRECIATE THE HELP
 
Also, the bible of Mobile Amateur Radio Installation is:

www.K0BG.com

Deals with every aspect.

My first post in your thread mirrors my use of this resource: be willing to keep untying the knot by mentally starting over.

Going over one’s install via his categories is the lowest-effort approach (believe it or not). Each category heading is a potential start over point (is how to approach it).

— The categories refer to each other, as each has a bearing on the other. One can go in circles.

There’s a beginning and an ending. End of Phase One (where you are) is that the equipment is installed and nothing’s blown up or caught fire.

Phase Two is verifying componentry is correctly installed, and (indeed) something or several somethings is off.

— RF BOND
— ANTENNA GROUND
are what I’d suspect from this distance.

Thus,

ANTENNA MOUNT

is where I’d open that mighty tome and make notes during the second reading. One might wander around with links the first go-thru, but go back to the DIRECT wording of this section.

Maybe it’s the most important section.

.

K0BG is considered a Mobile Setup GURU by many & he does his homework so others don't have to.He has helped me many times over the years at no cost.

SIX-SHOOTER
 
Bed is steel. I agree. I’m not in a rush I want it done right. Not half assed. I have gained patience. Worked outside in the Texas heat for 12 hours so I’m not touching it today. Yes I will get some pics tomorrow. Mount arrives tomorrow. Canceled coax order. Coax tested good.

REALLY APPRECIATE THE HELP



I had a feeling this was the case.

Do It Once, and Do It Right

Why my first post read as it did.

There are those who run past with their project, and then disappear back where they came from.


I’m in Fort Worth (well, I am when the Peterbilt is parked out front). Plenty of great mobile radio rigs the farther west one gets. But as many miles as I run it’s rare to hear a pickemup owner get out clearly & admirably.

“Loud & Proud, Hand”. (not the goal)

Hell, might as well be known as, Toothless from Arkansas, for the wretched noises produced when we tell them that. .

There’s nothing else like clean, clear audio — a voice coming off of a background of near silence — to wake up everyone else on AM-19.

Ha! Just ask if anyone has the time. It’ll go from silence to cacophony.

Recommend (strongly) you also take a look at the recent thread:

WEST MOUNTAIN RADIO ClearSpeech Speaker,

for when your wallet recovers. K0BG covers DSP in his guide.

Hear, and Get Heard

(is the real order of precedence, IMO).

.
 
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