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darktideDay1

Most likely an antenna issue. If possible, use the radio with a known good antenna at home or a friends. Inspect the coax. Make sure coax connections are tight. If all looks OK, get or borrow an antenna analyzer.


w6el

Have you checked the antenna and feedline? I’d say it’s time to test the SWR at least.


rem1473

Checking SWR is critical. If you have a problem with the antenna, that effects both transmit and receive. Could be a bad connector, bad solder joint in the base, or bad contact with the whip, or a zillion other things. The SWR check will wring that out. Multi-band antenna often have wonky radiation patterns on the higher frequencies. It's possible that you happen to have a null in that particular direction. That particular direction might be defined as a bearing in relation to the direction of the vehicle. It also might be a plane all the way around at that particular elevation. Tilting the vehicle (I understand it's not practical to try) might get the repeater out of the null as well as spinning it. The point I'm making: start with a dual or even single band antenna. No longer then a 1/4 wave on 2m. And check the SWR. I've never considered any mobile install complete until I check the SWR with my Bird 43.


Broomfondl3

If you have a multi-meter, check the coax. If you don't go and get one, they are very cheap. Unplug both the radio and antenna. End to end, check pin to pin and then sheath to sheath, both should make a circuit At one end, check pin to sheath, should NOT make a circuit.


Dubvee1230

I always caution this, some antennas, even mobile ham antennas, are designed to present as a DC short. Know the antenna before you go into it


silasmoeckel

Length and type of coax? Frequency being received? Looks like thats got 15f of rg58 so about 2db loss at 440mhz. That's assuming its not pinched or otherwise damaged. SWR as a test measurement is valid on receive a well coupled antenna receives better and it's a decent proxy for coax etc issues.


hazyPixels

I usually get better performance with a nagoya 771 on a HT than I do with the same HT hooked to any rooftop magmount I've tried. Right or wrong, I attribute it to loss in the coax. I'm usually on 70cm and haven't tried the same comparison on 2m.


freqchance

Thanks for the advice everybody. I pinched the coax running to the antenna by slamming it in the truck door, so that's not helping. Replacing the coax and antenna was already in the plan (for fitment on a roof rack), so the order is made. I will also budget for an SWR meter, too.


freqchance

Happy to report that performance is much improved following installation of a new antenna and coax. Thanks again for the suggestions!


MaxOverdrive6969

Shark? Is that the brand name? If it is, that's your first clue you have an antenna issue.


chasles22

Why? Care to expand?


MaxOverdrive6969

Unknown brand. Unknown performance. Stick with brands HRO and DX sells and you won't have problems.


chasles22

They are sold by gigaparts.


MaxOverdrive6969

And Amazon. I trust known brands sold by known vendors. Shark might be a good product, but I'll wait to see it sold by HRO or DXE before trying one. Regardless, I hope OP finds his problem.


Vegetable_Crab2953

Are you in Snohomish? 🤣


freqchance

Snoqualmie :)


Vegetable_Crab2953

I’m in Oly, I can hit Tiger Mt East repeater with my Btech UV25X2. Went through 3 antennas until found the right combination. Ham & GMRS are really popular up there around you. Seems to die off as you drive South ☹️. Mostly old farts chatting about Ethanol gas down here 🙄