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Well that sucks. If I ever went with a huge whip while driving, it would have to be a screwdriver and would need a massive mount. Too many people I know lost hamsticks or other large whips that way.

I have a TK-8180 and KRK-10. The stock ribbon cable between the face and body was part number E37-1120-05 and has description of FLAT CABLE (30P/TX-RX). You leave this ribbon in place and add a couple of folds when installing the KRK-10. The kit includes a new ribbon for the face side of the kit. Either way the description matches close the Pacparts part number 880H04-8897-72 which has description of Flex Cable (Display - Tx/Rx), that substitutes to 881H04-8116-92. It also looks the same as the original ribbon, which has no folds originally. The other ribbon shown in the service manual is E37-1110-05 and is called FLAT CABLE (30P/D-SUB). That connects the 25-pin D-Sub on the back to the PCB in the body. That description matches the other cable part number 880H04-8887-72 Flex Cable (Tx/Rx - D-Sub) that subs to 880H04-8115-72.

Hamsticks can show a closer to 1:1 due to their nature as shortened physically but 1/4λ electrically. So there's some coil loss. They have the same ground limitations as a full length antenna, though. BTW, remember SWR is logarithmic. So 1:1 means no reflection but 1.12:1 is only 0.32% reflected. IOW 100 watts in and 0.32 watts was reflected. At 1.5:1 you see 4% reflected, 2:1 reflection is about 10% and 3:1 about 25%.

Don't get too wrapped around the axle watching SWR. It's one aspect of tuning an antenna. It's important but having an absolutely perfect 1:1 SWR is no guarantee of a good antenna. A purely resistive dummy load will show 1:1 VSWR but radiates essentially zero RF energy. An incandescent light bulb will radiate more RF while showing a terrible SWR than a dummy load. For example, a 1/4λ monopole has a characteristic impedance of approximately 36Ω and thus a SWR that calculates to 1.38:1 when it's perfectly tuned for resonance with a 50Ω feed and actually exciting electrons well. In the real world a SWR from 1.1:1 to 1.5:1 for such an antenna indicates a very good antenna when you figure in non-ideal ground, coax loss, etc. In the impedance plot and Smith chart you'll see the effect of everything, the connectors, the coax, the antenna and its ground. That's the advantage of using a VNA or even just an SWR bridge or antenna tuner like the MFJ is that you can see the dip and trends. Point being it allows you to see if your measured values jive with your expected values. Point here is 108" (102" plus a 6" spring) is very close to 1/4λ for 10m (it is on 11m) so that you got 1.7:1 is actually about what you would expect. It'll never be 1:1 and if you get that it means you've added something that's absorbing energy to make it so, e.g. the capacitance that's been suggested. That's essentially building a matching network that's unnecessary in this case. If the antenna itself was not resonant or had a very high impedance (such as a 1/2λ end-fed, which has a VSWR of around 2kΩ at resonance) you have to impedance match to your radio. That's just what you have to do. But the matching network doesn't make the antenna any better, it just makes it so the 50Ω output of the radio doesn't see a big reflection that will cause damage or kick in protection circuits. But this is not necessary here. Your radio will have no trouble with a 1.7:1 SWR. It won't start to roll back power until about 3:1 in most cases and at 1.7:1 this antenna will be radiating all the energy it's capable of. Like I say, your measurement validates what you expected. Any matching will just be consuming energy and not helping make the antenna any better necessarily.

Seems like you could just use your 440 MHz / 70cm ham antenna with a coax switch. I've tested several of my hamband UHF antennas on GMRS and all seem to match up well enough. Vince

I believe one ribbon is for the KRK-10 and the other is for a front mount configuration.

Resonance and SWR are two different things. Resonance speaks to how closely tuned the antenna is the wavelength of the frequency you desire to operate on. SWR speaks to how closely the impedance of the antenna is to the characteristic impedance of your feed-line (e.g. coax). If the antenna is perfectly resonant, its impedance is exactly 50-ohms and the antenna is connected to a good 50-ohm coax, then your SWR will be 1:1. Now, if your antenna is perfectly resonant but it’s impedance is 75 ohms, you will never achieve a real SWR of 1:1 using 50-ohm coax. You cannot achieve it because there is an impedance mismatch between the two. You can trim and lengthen the antenna all you want, but you will never get to a 1:1 unless you add sufficient extra coax to eat up and waste all your reflected power (a waste). Hypothetically though, switch to a radio designed for 75-ohms, use 75 ohm coax and you are back in business, 1:1. A perfectly resonant antenna will absorb (i.e. radiate) all of the power you send it using the frequencies for which it is resonant, assuming off course you send it from a source and over feed-line that matches that of the antenna. When tuning an antenna you will see a nice SWR dip where the antenna is resonant because the impedance of antenna drops at the point it is resonant. The miraculous NanoVNA can be your friend because it affords you the ability to calibrate to the point of antenna connection, then focus on analyzing the antenna itself to see what it’s actual doing, seeing what its real impedance is. Other analyzers can be just as useful. In using one of these at the antenna you can see the effect of every change you make, from moving it, mounting, nearby surfaces, lengthening and shortening. All in all, 1.6:1 to 1.7:1 are not bad at all. So, except for the learning you would achieve, I see no critical reason to fret about the values you have listed. Michael WRHS965 KE8PLM

Newbies may also start with Maxwell equations (https://en.wikipedia.org/wiki/Maxwell%27s_equations). Learning is good, right? It's like a dancing lesson offered by Lord! Snark off: I still think that when somebody asks about "decent cheap SWR meter" the NanoVNA is a wrong answer. With all due respect to the NanoVNA and those who offered the advice.

Help. How do I go back home from the forums page. I am sure it's obvious but I cannot figure it out. Thanks.

Current update. This morning on the way to work the antenna and 1/2 the nmo decided to divorce me on the highway. It went flying off and promptly got destroyed by the car following me. So new mount for further down the 1/4 panel, going to use the 5/8ths fire ring mount.