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I don’t recall ever saying that you are using the wrong coax. I pointed out that RG8x has a foam dielectric and RG58 has a solid dielectric and that’s why RG58 is frequently used for mobile installations. RG400 also has a solid dielectric and a tiny outside diameter. It’s expensive though. A person could build a Frankenstein cable using RG400 where needed and something with less attenuation elsewhere to make up the necessary length, but the splice points reduce reliability and potentially add losses. Also, nothing I’ve said has been demeaning or critical of you or in any way personal. I’ve tried to stick to factual information, demonstrating how I did any calculations.

I’ve been meaning to grab some for a long time now. I think you’ve got me motivated to pull the trigger finally.

Im just trying to help and little, but i think there is benefit to watching this video. I put it together for some new Hams in my club, but the Amateur frequencies in UHF are close enough to GMRS, that the demo is still very valid.

Exactly. So, what's the point of telling me I'm using the "wrong" coax? I'm sure ladder line would give better results, but it won't fit through the holes in the floor of the back of the cab, to say nothing of going under the side bed rail, over the top of the front bed rail, down the front of the bed, under the cab, and back up through the hole in the floor. 15' is about as short as I can go and it has to be very flexible. I'm not aware of anything "better", but I'm open to suggestions.

Hey, just trying to spread some love. I know some people here might not seem like they love each other, but think of it this way, it can be just as difficult picking the right coax. No shame in selecting the wrong coax, just admitting to yourself you made a poor choice is the first step towards inner peace.

I reran the numbers using RG-58, RG-8X, and RG-8 with the length of 15 feet since that is the average length used in vehicle installations. RG-58 RG-8X RG-8 Now most mobile antennas will not have 5 dBd of gain so you will have to adjust that number using the calculator.

I'll be civil to him when he stops being an ass.

That's nice to know, but LMR400 and Heliax aren't practical for vehicle installations.

Come on now. Please be civil as this is a family oriented forum.

I'll look at that for next time. In the meantime, I'm not having any more line loss than 99% of the installations out there. Less than most, in fact.

Kind of irrelevant since most of us won't be using 100 meters of either in our mobile instalation anyway. Again, using the right coax for the job is key.

No, you illiterate. I specifically stated that it's an NGP antenna. But even an NGP antenna can often benefit from a good ground plane.

Yes the codes I used were simply fake to as not confuse anyone. But thank you for the explanation, I go it!

I ran the numbers using the https://kv5r.com/ham-radio/coax-loss-calculator/ for several types of coax. Here are some screen shots showing the losses for 100ft of coax. LMR400 RG-8X RG-8 1/2" Heliax

The Signal sticks come with male and female SMA connectors as well as BNC. I use the signal stick on all my HTs.

The spec sheet for the RG400 cable shows a loss of 28.3 dB at 400MHz per 100 meters. RG8X has a 26.25 dB loss per 100 meters at 400 MHz.

Just buy a good antenna and atleast lmr400, or better, and hand the antenna. It’s not rocket science

I may not have privilege to talk on the LEARN system, but I don't need permission to monitor the LEARN system. Besides, some of those individuals sound as if they're want to be Law Enforcement Officers. Maybe a few of them were actually LEOs, but they certainly overdo it with using Ten Codes. Anyway, one of those LEARN members always manage to fail to identify his station with his FCC Call-Sign. Of course, I can't say anything since I'm not allowed the key up. Sometimes, I feel like saying something, but I know a certain individual call on the phone and chew me out.

As stated above, RG400 MIL spec Teflon dielectric with silver plated copper conductors. Perfect for mobile installation and works great with the world famous and highly cherished NMO mount. In other words, pure perfection. And here ya go, an already made cable that's ready for installation and it even has the dreaded PL-259. https://www.ebay.com/itm/375935266177

You Just Posted It..... Another Attitude - Please Re-read My Post - Or Not...... Peace Out.....

Antennas typically consist of reactive elements and radiating elements. The reactive elements are used to match the impedance of the radio and feedline which is usually 50 ohms. The radiating element is one or more metal wires or rods that convert the signal into RF. It’s usually the most visible part of the antenna.

How do we "loose" an attitude? And which one is it? Should we stop discussing this stuff or should we share our knowledge and experience? I'm confused.

OMG..... Unbelievable.... Maybe All You Folks Should Consider Talking On Your Radio Stations Instead Of Constantly Arguing, Bickering, & Discussing On How They Are Supposed To Perform Better According To Your Opinionated Logic Of The GMRS / UHF Frequency Band, & Everything Else Involved....... Not Sure What Else To Say, But It's A Pretty Sad Rendition Of Folks That Should & Definitely Know Better With All The Knowledge That Exists On This Form. Folks Just Need To Loose Their Attitudes & Share Their Supported Knowledge........ Thx Bob Somers - WRXL702

RG58 is used because the dielectric is solid and doesn’t deform like foam dielectrics, but you’re right that it’s even lossier than RG8x. Choosing cables for a mobile installation is a juggling act. The only cables that will withstand being pinched in a door are thin and stiff because of solid dielectric materials. But they’re also very lossy. So you minimize the length as much as possible and accept that they aren’t ideal.

I picked 10:1 as an example to demonstrate how SWR readings can be completely misleading when made through lossy cable, not as any assumption of the SWR of your antenna. Th right tests are important, but tests can be very misleading. If you want to know the SWR of your antenna, measure it at the antenna feed point, not at the radio. If you want to see how well your cable works, SWR of antenna and cable combination isn’t really an ideal test. Test the cable with a dummy load at the end. Test the SWR of the antenna separately. And put a power meter next to the antenna and then next to the radio and compare the results to see how much power is lost.