SteveShannon

Without knowing what is really in that tube I’m not certain. It could be a couple pieces of wire with a trap between them. If that’s so I would think (low confidence!!!) that the first (lower) wire is the UHF element and both elements together form the VHF element. The trap serves as a conductor at the lower frequencies so the two wires are connected together and becomes high impedance at UHF frequencies so only the bottom wire is the radiator. The difference between full wave GMRS and 70 cm is just a few centimeters and if the UHF antenna is intended to be a quarter wave it would be a quarter of that. But I don’t know if you can get the fiberglass radome off the base anyway. Mine appears to be epoxied.

Yes, remove the bolts that hold the bottom tube on and you can easily get to the coax connector which is probably just a pl-259 on the cable and so-239 on bottom of the antenna.

This! Nano VNASaver is just so much easier to use and gets you more easily viewed results.

I would get it. If nothing else the parts can be scavenged. That looks a lot like the Comet dual band Antenna I have which works very well. It also looks like they have a pretty long length of coax that might be worthless for GMRS but usable for lower frequencies.

Not at all. In amateur radio it’s not terribly unusual to work split like that.

Thanks, that’s very helpful. So each repeater is capable of receiving on two different frequencies and repeating on one. Interesting. I learned something new today. I’d like to hear from someone who actually has tried it.

The problem is that it results in an infinite loop, going right back to the first repeater.

If you choose not to comply with regulations that’s your choice, but it’s wrong to belittle someone else who does a good job of explaining the regulations to someone who might not understand them.

I agree. When I bought my first DMR radio the fact that it could store 200,000 contacts seemed important. Since the I can count on three or four fingers how many times I have actually downloaded the list and loaded it into my radio. Of course within months 200,000 wasn’t enough, so the second time I chose to just load European and North America. Then just North America. Now, I don’t even bother.

I can only speculate, but perhaps they reserve the air band radio for conversations with the tower and leave it tuned to that frequency. Chit chat on GMRS doesn’t affect that.

95.307…Operation of Personal Radio Service stations in any location outside of those described in the following paragraphs is not authorized by this part. (B)Aboard any vessel or aircraft registered in the United States. With the permission of the captain, while the vessel or aircraft is within or over the United States or its territories, U.S. territorial waters, or upon or over international waters. So, it appears it’s allowed.

SWR is somewhat important, but tells you nothing about gain or pattern. A dummy load will test nearly perfectly for SWR.

This! Testing the SWR of a handheld radio antenna is either very tricky or useless, depending upon whom you listen to. Performance is what matters.

Almost certainly. Ratings are usually conservative. Plus, you probably don’t transmit continuously for long periods of time.

They are two separate logins, but once you’ve logged into both you should be okay.

Welcome to the forums!

Personally I wouldn’t use either one of those. I would buy a better known brand such as ABR, M&P, DX Engineering, Times-Microwave, Belden, etc. The way to make certain you’re getting a quality product is to buy from a vendor you trust to provide quality products. If you buy an unknown cable from an unknown vendor on Amazon you’re completely responsible for assessing the quality.

Losses through any coax go up as the frequency goes up. RG-58 is terrible for UHF. RG8x is better than RG58 but still poor compared to something like LMR400. Each person must calculate what the actual losses will be and decide whether they can afford that amount of losses. What’s worse, the losses are expressed in decibels which can be confusing until you become familiar. A loss of 3 decibels means you lost 50%. A loss of 6 decibels means you lost 75%. Every coax company has charts that show us how much loss they have at a particular frequency, usually for 100 feet or 100 meters. Be careful not to compare the two. A meter is more than three feet. Losses increase with length as well but that’s a linear relationship: twice as long equals twice the losses if the frequency is the same. Most of us find a calculator online to calculate the losses at the exact frequency and length of the type of cable you’re looking at. Just google “coax loss calculator“ and you’ll find one. This is the most common one: https://kv5r.com/ham-radio/coax-loss-calculator/

That’l learn ‘em!

Be sure you do the math to figure out the losses in 25 feet of RG8x for the highest frequencies you intend to use. It could be substantial. RG8x is fine for HF, but lossy for 70 cm.

GMRS is not a “public service”. It is a Personal Radio Service. You’re right that people shouldn’t be making a profit from charging to use their repeaters. The regulations allow recovering expenses only.

Will do, Gil. Of course everything multi-band is a compromise. I wouldn’t mind testing it with some single band whips.

I have a Diamond RH77CA with a BNC connector on my FT5DR. It works when shorter antennas just don’t, but I don’t have access to a large number of antennas like the HRCC video tested. https://www.dxengineering.com/parts/dmn-rh77ca I wouldn’t mind picking up a different Tri-band antenna for my VX-6 and I’d really like to get a decent four band 6 m, 2 m, 1.25 m and 70 cm antenna for my VX-7.

No, not at all.