Lscott

They are real antennas, and they do work.

Some of the frequencies are in consecutive steps of exactly 100KHz too, so it's not even based on some standard channel spacing either. My first guess is these were "test" frequencies used to "tune" the radio's PLL circuits. I know my commercial radios have a special bank of frequencies just for that purpose. The attached photo is from my NX-1300 for example.

Ah, that's a very useful link for this! The take-a-way is there are such grandfathered GMRS business users out there.

What did you use to test the SWR? I've done some testing myself using a Rigexpert AA-1000 and didn't get great results with the 7500. The comet CA-2xSR did reasonably well. My old Comet dual band CA-2x4MB is the best one I've had, but it's not manufactured anymore. These antennas are sensitive to the type and location of the mount being used. Particularly the CA-2xSR. I currently have the CA-2x4MB on my Mazda. The fold-over spring is weak so I have the antenna permanently taped so it doesn't flip over while driving. I have a spare brand new one still in the green plastic packaging. The antenna is about 60 inches tall so I have to be EXTRA careful where I drive. https://forums.mygmrs.com/gallery/image/471-mobile-mount-with-antenna-rear-view/?context=new https://forums.mygmrs.com/gallery/image/473-close-up-of-mobile-mount/ And this is when I had it on the old Jeep. https://forums.mygmrs.com/gallery/image/259-ca-2x4mb-jeepjpg/?context=new Antenna Scan Results (CA-2x4MB VHF Jeep).pdf Antenna Scan Results (CA-2x4MB UHF Jeep).pdf Antenna Scan Results (CA-2x4MB MURS Jeep).pdf Antenna Scan Results (CA-2x4MB FRS_GMRS Jeep).pdf CA-2x4SR VHF TRI MAG MNT.pdf CA-2x4SR UHF TRI MAG MNT.pdf SG7500A VHF Scan GND Radials.pdf SG7500A UHF Scan GND Radials.pdf

I think before that question it's important to understand what it is, and isn't. There is a good write-up at this link. https://en.wikipedia.org/wiki/J-pole_antenna Most of the issues with the antenna stems from it's radiation pattern. Depending on construction and installation the antenna may present some noticeable asymmetric gain characteristics. One other important point is the antenna requires some kind of "decoupling" network for the connecting coax cable. That's typically done using some snap on ferrite cores very close to the feed point, or a coiled up section of the coax cable. If this isn't done then all sorts of weird highly asymmetric gain characteristics may occur along with high SWR readings, and even RF getting back into the radio causing distorted audio.

Likely they would complain anyway if it was just FM and some real chatty users had the other repeater keyed up for long periods.

One other course is if the repeater is located on a commercial, for rent, tower the owner of the tower may not want that repeater there if it's operating illegally. If nothing else works then likely you may need to hijack the repeater unless it's locked down by the SU's, subscriber unit, electronic serial number or other access restriction method. It might not matter if the unauthorized traffic is encrypted or not from the hijacker. If it has to run encrypted chances are it's RC4, which is compatible with Motorola's enhanced privacy and other manufacture's 40 bit encryption. I have my Kenwood NX-1300's enabled for it if I really need the feature. https://forums.mygmrs.com/gallery/image/290-nx-1300duk5/?context=new Some of the older Motorola radios have it enabled as a freebie on the HT's. https://forums.mygmrs.com/gallery/image/261-motorola-xpr6550jpeg/?context=new The idea is to use it enough to annoy the owner(s) to shut it down and move it. If the FCC isn't interested enough to do something about it they likely won't bother the people hijacking it either. While not ethical, and not legal to use DMR by the business or hijacking users, the FCC has invited the activity by their lack of rules enforcement. Your choices and options are rather limited.

Hum.... If it's operating illegally then I suppose they really couldn't complain if it got hijacked by local GMRS users. If they did the FCC might take more of an interest in it and ask a lot of questions they would rather not answer. Their other choice is to shut it down and apply for a legitimate business frequency and move it there. And SDR dongle with the decoding software, or one of those D878UV's using the digital monitor function, will show you all the color codes, slot numbers, talk groups and user ID's on the repeater. While the D878UV might not be that great of a radio the digital monitor feature is one of it's very useful one's for getting info on unknown DMR traffic.

You sure it's really operating illegally? Remember before the 2017 rule changes business could get a GMRS license. So long as the business has maintained their license, didn't let it expire, they can continue to renew it and operate LEGALLY. The only way to find out is locate the business in the FCC's database, assuming it exists, and if so is their license still active.

The resistivity of platinum is far worse than copper. At UHF frequencies the skin depth of the RF is so shallow the underlying material doesn’t really affect things. https://www.thoughtco.com/table-of-electrical-resistivity-conductivity-608499 https://en.wikipedia.org/wiki/Skin_effect

The few who had too many beers before hand likely didn’t make it to the prom I’m guessing. It’s hard to leave the house when you can’t find the door.

I'm guessing before the rule changes GMRS licenses could be assigned to businesses. That would have been the attraction for the dual 90/95 certification. Now with the new rules it's only for individual users, unless the business has a grandfathered license they kept current.

Thanks for the link. That's the very first radio I've seen that covers the full Ham band, 400-470 MHz split, with a Part 95 certification. Now that's way cool. I have a collection of various Kenwood HT's, with the same split, but NONE have Part 95. The exact same model with the typical commercial frequency split, 450-490/520 MHz, do have it. I had always assumed if the radio covered 400-470 the FCC would not grant Part 95 certification. I guess my assumption was wrong. Yeah the MARS/CAP mod at times isn't all that great if you can't get crap for power out. I ran across some power tests done on a Icom IC-706MKIIG with similar results, sort of sucked on GMRS. IC-706MKIIG Freqequency Mod Power Output.pdf

I want to check on that. I had a total knee joint replacement done a year ago last August. Wore out the joint, it messed up when I was on the leg press machine doing my usual full weight stack setting, meniscus was half gone per the doctor when I finally went in. I get around OK now and do about 30 minutes on the exercise bike 3 times a week, and weight lifting. The trike might be a good option in case the knee gets a bit stiff and less likely to take a spill.

"Let's have a moment of silence for all those Americans who are stuck in traffic on their way to the gym to ride the stationary bicycles." Funny as heck to see people try to park as close to the gym entrance as possible to avoid walking more than necessary to get in. Then get inside and run for an hour on the treadmill like a hamster in a wheel for an hour. Never could figure that out.

How much did the trike cost you? Looks much more comfortable to ride than a standard 2 wheeler. More room to mount stuff too.

If the G6, 400-470 split, has Part 95, it will be the first one I’ve seen.

You can, BUT Ham band specific radios MAY experience a significant power output and receive sensitivity loss outside of the official Ham bands. That's due to the internal band pass filters. For example my old original Yeasu FT-817 QRP rig is modified. It's a nominal 5 watt radio on the Ham VHF/UHF bands. I'm lucky to get maybe a watt or so out of it on the 467 MHz GMRS repeater input frequencies. Hardly worth the trouble. I'm way better off using one of my 4/5 watt commercial HT's designed for either 400-470 or 450-490/520 MHz band split operation. With the 400-470 MHz band split I can at least use it on the full Ham 70cm band and GMRS. Some of the older commercial grade radios are certified for Part 95, the 450-490/520 MHz band split, so they are legal to use with proper programming. I'm not familiar with the commercial grade base/mobile radios, I use mostly HT's. https://forums.mygmrs.com/gallery/image/468-tk-370gjpg/?context=new https://forums.mygmrs.com/gallery/image/263-tk-3170jpg/?context=new https://forums.mygmrs.com/gallery/image/254-tk-5320-1jpg/?context=new The commercial grade radios with the 400-470 MHz band split are not Part 95 certified from my experience, just Part 90, at least I've never seen one that was.

Many Many years ago I had a buddy who got a speeding ticket on his 15 speed bike for exceeding 25 MPH on a residential street. Yeah, it really happened.

When I ran my IC-706MKIIG in a van I used a single sided head set with a boom mic for the exact above reason. The radio was setup for VOX for "Hands Free" operation.

Yes you can. Go to the FCC Manager Help page and scroll down a bit to the "Contact Information" section: https://wireless2.fcc.gov/helpfiles/licensemanager/commonQuestions.html

Nothing prohibits it. Some people dislike the idea of GMRS turning into a sort of "Ham Lite" service, but if nobody is breaking the rules so who really cares?

I'll look into those. Heil Sound is well regarded. The price isn't bad either. Thanks.

https://www.imdb.com/title/tt0047577/ It was a decent movie except for the cheesy rubber suited monster.