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OK Boyz and Girlz, here we go. I opened up the Btech RPT50 repeater to remove the original wideband duplexer First thing I did was check the output wattage from the transmitter. The power supply was set at 13.8 volts and it was putting out 71 watts into the duplexer. Had 42 watts out of the duplexer. And not the best SWR on my 50 ohm dummy load. Right at the edge of spec. I turned the voltage down to about 11.5 volts and it showed about 65 watts out. Probably the lowest I can get it. Then I swapped the original wideband duplexer for the one that Marc so graciously tune to a single frequency for me (600). I relabeled it so some future person doesn't think it's wideband. I should probably strip the other frequencies out of the channel selection also. And I tested it and got about 48 watts from it. I said what the heck and boosted the voltage a bit and got it to put out 50 watts. I haven't put it back into service yet, soon. And testing won't be done until it cools off from the 98ºF it currently is. Says it's going to be low 70s tonight. Probably be to excited to test things at midnight, so likely around 10 or so I walk my route. Of course I'll key it up on the way home, at home on the base and try an HT from inside the air conditioned house. LOL Most of the duplexers I looked at said "40-80 watts (50 watts)" so hopefully I don't melt this one. The replacement was accepting the 71 watts without blinking and the original had the power supply set for 12.5 volts which is about 67 watts into the duplexer.

The attached file is an example I did to do a hex edit hack on a Kenwood NX-411 code plug to get on the Ham 33cm band. The radio programming software wouldn't allow the entry of the frequencies. How to Hex edit Kenwood code plugs - 20241011.pdf

You need to get a windows hex editor. Then you can load in the binary file and edit the specific memory location. https://en.wikipedia.org/wiki/Hex_editor https://www.av-rd.com/knowhow/data/hexedit_archivists-1.html

Good edit!

Reminds me of shooting at the range. There are some long-range rifle shooters who consider clays (trap/skeet/sporting clays) to be beneath them. "I shoot at 1,000 yards. What's a long clay shot, 50 yards? Pfft. Too easy." I'd love to get him on the skeet range with a ringer, a 14 year-old girl who recently hit 197 out of 200 at a national tournament.

Well I am actually going to find that out tonight. I have a Btech 50w repeater and it has a wideband duplexer in it and soon I will be changing that out for a single channel tuned duplexer. The receive should be more sensitive. The receiver will be the same, but the desense should be much less with the >-85db vs the >-45db of the wideband duplexer

True. Well OK, but the RX sensitivity at the antenna connector is what matters. Do we know anything about how good or not that is? ps: yes IM, Adjacent Channel etc matter in some installations too

Checking first, are these lines of data/code that I am modifying? And thanks for the reply.

I have experienced what Marc described, but I learned to avoid them so it has no impact on me. If they are becoming less common it's mostly because the old farts are dying out. Adding to what Marc described, a lot of HAMs want to only have meaningless social chat, which is not what I got radios for. I deleted all the nearby repeaters from my channels because I'm fed up with these people. I asked about joining a club in my hometown and was told no, to start my own. After I moved I went to the nearest club meeting and was mocked for only doing 2m (and 440). I've asked about starting nets twice and was turned down. Gave up on ARES when they made training and deployment as criteria. Skywarn was moved to a repeater I won't use because of policy. Really nothing left for me on HAM. GMRS turned out to be disappointing as well, but I monitor it more now than HAM. Back on topic, there is a new GMRS repeater only up 30ft but the owner wants to link to a node (did he miss all the brouhaha?). Same frequency used by other repeaters that likely overlap his area. From what I recall the linked system owner shut down so I don't know why this is even still available.

Or I got luck and got one that was fairly accurate. I have two of them and they both read the same for power and SWR. I had one on my home base and when I got the new one I swapped out to see if it would read the same. It did, so I didn't even swap them back. Just took the older one and it'll go into my shop setup.

Not going to be the receiver sensitivity that'll be the issue. The wideband duplexer is what is really going to limit the sensitivity.

I agree. Fortunately, the behavior that Marc described is becoming less common, at least in my area. I don’t know of any hams in our club who look down their noses at GMRS licensees, but most of us would be very happy to help an interested GMRS licensee become a ham also. For any widespread emergencies amateur radio has an advantage, but for nearby emergency communications GMRS and FRS are much more easily accessible to more people. Ham clubs should be studying how these services can be complementary to each other.

That is just sad. I guess that is where Randy came up with the term "sad ham." I have been very fortunate that I have not had such experiences. All the hams I associate with are very good people. And many of them are dual licensed.

The problem with the whole concept of teaming up with an amateur radio club is that some amateur radio operators despise people with a lower level license than them. There's no way they would accept somebody from the gmrs service as deserving of their time. I have a general class amateur radio license. I am what is lovingly referred to as a no code General Tech. It's a dig that General and extra class license holders use to insult General class license holders who did not have to pass the morse code requirements. I have literally had dozens of experiences where General class license holders who passed their Morse Code test and extra class license holders who have passed there Morse Code test found out that I was a no code General and stopped talking to me in the middle of a conversation because I wasn't worthy of their time. While there is a good amount of people in the amateur world who are absolutely amazing at Radio stuff and love to share their knowledge, there are way more people who are just grumpy old sour pusses who would rather cut a finger off than help someone who isn't "worthy of their time."

Maybe they fixed it in the past six years…

I wonder how good the RX sensitivity is on the 97L. I read somewhere that it's spec'd at 0.35uV, compared to 0.20uV for the 97S. Any one know if this is correct? ps: I hope not as 0.35uV is not very good for a repeater. It would have a hard time hearing the HT's when far out but the 20+W TX would get to them well. thanks for any info.

There's a good observation here: "ham vs GMRS" doesn't help. People wanting to establish a good GMRS repeater would get a lot more traction on such projects by working *with* a ham club. In my area there are a lot of really good 2m and 70cm repeaters. And the groups operating those repeaters have solved a lot of the hard problems. If you can build a good relationship with them, you might get help navigating the waters of setting up a GMRS repeater.

My Surecom 102 seems to be pretty accurate. 4.7 on a 5w HT, 48w on a 50w mobile, 25w on a 20w mobile. Might not be perfect but seems close enough.

All they have to do is put "up to" and there ya go.

Others have posted VG info already, won't add to that. I do know a couple "professional" storm chasers, they both have LMR licenses for their pursuits. Mostly so they can encrypt their radio traffic, so as to not have other chasers, especially those who take groups out to show off storms, their info.

It certainly would. I ran a center mag-mount CB whip for years on another truck, but hated having the cord so visible and really hated what the mount did to the paint. Drilling a hole in the roof and moving my NMO mount there would also be better, but I’m not drilling a hole in this truck. I’m already getting into repeaters >20mi away on my 778II, so I’ll stick with this low-profile setup.

If you get a mag mount on the roof it would likely perform even better.... i run one of the chinese copies of the midland on my car, and can get 20+ miles to the local repeater with no issues with my 778uvII

See attached file and read the instructions below I had found on-line some time back. ==================================================================================== KPG49D v4.02 Password Bypass -> KPG49D.exe: 0x0000418A change 74 to EB Once modified, when the Data Password dialog box opens, just hit enter or type anything and it will then go onto read the codeplug. The password is located in the .dat file at 0xB5-0xBA. KPG-49D V4.02.zip

Of that I am very aware. These are mostly leaf trees so there's that.... Always had issues from the house to the shop which holds the repeater. 50w vs 25w. I could always come in mostly clear to the house, but from the house it was hit or miss. Then I got a 50w radio for the house and the problem is mostly gone, certainly not R9 reception but easy to talk and understand. Needed the extra wattage to punch through the leaves it seems. On top of that what helped later on was swapping out to the Comet 712EFC. Eventually the repeater will have that same antenna and upgrade from the Retevis 7.2dBi. So sometimes a little more wattage works. And since the 1st wideband duplexer was swapped out for the 2nd wideband duplexer I've been able to hit the repeater mostly successful with a 5w HT. R7 at best, no communication at worst. Duplexer is coming in today

It would be very hard to find a mass produced antenna with so much gain that it would cast its signal too high or too low for another antenna at a 140 foot offset 20 miles away. That's 0.00135%, or 0.076 degrees. That level of focus of signal is in the realm of laser beams, or antennas for communicating with equipment on the moon. Another way of looking at it is that a boat's radar, which is designed to have good resolution characteristics, could merge two objects into one if they're less than 300 feet apart at 20 miles.