SteveShannon

Great first post! Welcome to the forum.

A mobile station installed in a house (fixed location) and communicating only to other mobile stations in fixed locations would be fixed stations. Of course all those mobile stations would have to comply with the other rules regarding fixed stations, such as power output.

Your understanding is incorrect. You may only transmit on the 467 MHz frequencies when communicating through a repeater, for doing very limited testing, or between two fixed stations.

Specs and drawing of Pasternak N barrel connector. VSWR maximum of 1.3:1 from DC to 11 GHz. https://www.pasternack.com/images/ProductPDF/PE9006.pdf They have others at up to $96 apiece that are 1.2:1 up to 6 GHz. Unsurprisingly, their UHF bulkhead connectors are rated 1.3:1 but only up to 300 MHz. We really should all be using something other than UHF connectors for GMRS or 70 cm.

Yes, I knew exactly what you meant when you discussed using air as the dielectric. I could do a two port analysis also from one end to the other. But probably not today. ? Also I would want to look at N barrel connectors.

Thanks! I studied it for a while. That helps, but I’m even more curious how one would look on an analyzer to see how one tests versus theory. Theoretically they should be close! ? Happy Easter!

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I’d be interested in seeing what one of the eight inch barrel connectors looks like on an analyzer.

Simplex is not prohibited on the 467 MHz channels. The regulation doesn’t even imply that. The regulation simply limits which radios can converse with each other in those channels. Two fixed stations could chat with each other in simplex all day long on 467 MHz channels.

It really depends on where you are and what you’re doing. I only use GMRS to talk to friends and family when we’re engaged in a shared activity, such as at a rocket launch or on a hike. I don’t have any interest in random conversations on GMRS with people I don’t know. To me that’s something I would do within my ham activities. I only use my call sign on GMRS to be legal. Everyone in my group use first names.

When you change from channel or memory mode to frequency mode, the frequency does not correlate to the channel. It’s the last frequency you were on. For instance, you tune your radio to 443.675 and then you change to memory mode. The last channel you were on in channel mode is where you’ll be. Then change to a different channel. Then, if you change back to frequency mode, you’ll be right back at 443.675, the frequency you were using before changing modes.

Never mind the fact that Huawei actually makes chips designed to connect wirelessly to the internet and manufacturers were buying them by the literal boatload and embedding them in computers where their owners were telling them their SSIDs and passwords and where they were ideally situated to spy on whatever activity took place on the computer. Never mind the fact that your cellphone is also connected full time to a network and has a gps built in and carries your most intimate pictures and messages. If you fear your Baofeng UV5R then logic dictates you simply must avoid every Chinese made electronic device, because they are all being manufactured under the same control of the Chinese Communist government that would co-opt Baofeng. Fortunately, my Garmin was made in Taiwan.

You are. But not all of the FRS frequencies are limited to 0.5 w ERP. Why not use the frequencies that allow 5 watts? Here are the frequencies: https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-95/subpart-E/section-95.1763 Here are the power limits: https://www.ecfr.gov/current/title-47/section-95.1767

LMR-400 loses 2.8 dB/100 feet or 1.82 dB at 65 feet. The insertion loss for that duplexer (from the B2WR website) is 2 dB. 1.8 plus 2 is 3.8 dB, so you lose 58% of your power between the radio and antenna. Here's a discussion about that same duplexer from about a year and a half ago:

ARRL is not the only organization recognized as a testing organization, although they might be the largest in the USA. There are 14 Volunteer Exam Coordinators recognized by the FCC I’m a volunteer examiner for the Laurel VEC. They have a lot of test locations every month. Check their schedule at LaurelVEC.com. Click on “Exam Schedule” on the left.

Dumbest thread ever.

You’re only putting out 31 watts on transmit as well as receive? On receive your SWR/wattmeter should show nothing. Presumably one radio is set to be the transmitter and one is set to act as the receiver with the two radios both connecting to the duplexer, the transmitter connected to the 462.xxx input and the receiver connected to the port that allows 467.xxx to pass. The third port on the duplexer goes to the antenna. As @gortex2 alluded, the tuning of the duplexer is key to getting everything working together. Where is your SWR/wattmeter connected? If it’s directly connected at the output of the transmit radio, it should be closer to 50 watts, but probably still somewhere in the 40s. If it’s connected at the 462.xxx input of the duplexer the wattmeter will read whatever power is left after cable losses. If it’s connected at the antenna side of the duplexer it will reflect insertion loss through the duplexer as well as cable losses to the duplexer, and if you connected it at the antenna it will read losses through two different cables as well as insertion loss through the duplexer. And finally, if you connected the wattmeter at the 467.xxx port of the duplexer you shouldn’t see any power at all. What kind of coax are you using? What’s the length? What kind of duplexer is it? If you’re measuring at the output of the duplexer, and depending on the type of duplexer, 31 watts out could be reasonable. As @OffRoaderX commented the low audio could be caused by transmitting narrow band and receiving it on a radio set for wide band.

Welcome! As @BoxCar said, it doesn’t work that way. Full duplex analog repeaters simultaneously transmit what they receive using one frequency to receive and another to transmit. They do no routing and they do not pass along signals. In GMRS, full duplex repeaters receive on 467.xxx MHz and transmit on 462.xxx MHz so they cannot hear each other. Networked GMRS repeaters are connected via the Internet and in some instances are subject to transmitted commands to join the network, but I have no idea how routing works (or if it does). Due to their public nature, though, if you routed a networked repeater everyone else using the repeater goes along with you and, conversely, if they are allowed to command the repeater you’re using to re-connect to another networked repeater mid conversation, off you go. And of course in an emergency that involves an Internet outage all networking fails. Although I have no experience using networked GMRS repeaters, I do have experience using DMR repeaters in the amateur radio service (ARS). There you connect via Talk Groups. Depending on which network your repeater is linked to, you can talk to someone else on another repeater connected to the same network anywhere in the world as long as they know to listen at that time. Calling them on the phone works for arranging that. ? Of course everyone else connected to either repeater on either end hears you and can even join your conversation. Neither GMRS nor ARS has anything remotely resembling secure and private conversations.

I would suggest that you get some experience and education before building a rolling NSA station designed to cover every frequency. There might really not be any need and by adding all of the frequencies and limiting the number of antennas you want as bristles on your vehicle, you are constraining yourself to compromises somewhere. Why do you want to cover MURS? Why do you want to cover 1.25m? Are they truly important to you? Do you need to transmit on them all or just be able to monitor them? Especially for mobile use you probably don't need to cover that much. In any kind of communications plan for emergency use you will probably want to restrict your activities to one or two specific frequencies or you stand the risk of never finding someone. Another thought is that there are antenna systems where you swap out the element to concentrate on a single band at a time. They are available for 80 meters through 6 meters and can even be combined for greater versatility. They're sometimes called Ham Sticks. Shark is one of the vendors carried by Gigaparts: https://www.gigaparts.com/nsearch/?lp=SHARK

Are you having trouble finding a club? It would appear that the area is pretty active. In May the Hagerstown Hamfest will be held: http://www.arrl.org/hamfests/the-great-hagerstown-hamfest-4

And that’s with Belden RG-8x, which is quality. It’s a characteristic of the cable and proportionate to length, and it’s simply not possible that you would have a 50 foot RG-8x cable that doesn’t have much loss at GMRS frequencies. There are lots of accounts of really terrible performance from the cheap gray RG-8x or RG-8 mini from Amazon.

Those are very good pictures. Based on those sweeps, if I wanted one antenna to cover the greatest range (albeit not the lowest SWR on all bands) VHF amateur and MURS and UHF Amateur and GMRS, the Comet would be a good choice. That’s very helpful. Thanks!

The screenshots from NanoVNA Saver are usually pretty good and while the NanoVNA isn’t labrotory grade as long as it’s calibrated for each band beforehand the results are very usable. Sure, I’d like to have a RigExpert Zoom 1500, and maybe I will get a RigExpert Zoom 650, but the NanoVNA isn’t total garbage.

So one more level of organization than DMR? So, when you add selections to zones are you including the entire Personal group of individual channels or do you assign channels to zones individually?

I would be interested in seeing the graphs.