SteveShannon

Well, there’s this: 95.1749 GMRS network connection. Operation of a GMRS station with a telephone connection is prohibited, as in § 95.349. GMRS repeater, base and fixed stations, however, may be connected to the public switched network or other networks for the sole purpose of operation by remote control pursuant to § 95.1745.

Here’s a short thread from last year about connecting a speaker output to a car audio system, similar to what you’re doing. In his first post, the OP includes a link to a “speaker to line level” adapter to handle the concern I raised. That probably offers a degree of isolation as well. Here’s the converter: https://www.amazon.com/dp/B07VKFSLKN/ Here’s the thread:

A data sheet for a high quality SMA male connector shows that the center pin may be beryllium copper, which is not attracted to a magnet. https://www.fairviewmicrowave.com/images/productPDF/SC7033.pdf Magnetic properties of beryllium copper: https://materion.com/-/media/files/alloy/tech-briefs/at0006-0311---tech-briefs---magnetic-properties-of-copper-beryllium.pdf

Looking at a drawing of one type of female SMA, which has a solder cup on the other end of the center pin socket, it appears that the pin cannot go into the radio. If it could then opening the radio and pushing the pin through would be the way to go.

It might be rough on the radio but the only way I can think of would be inertia. Tap the antenna jack with a plastic mallet and check often to see if it’s working its way out. Once it’s poking out slightly maybe you can pull it out.

Your phone output goes to earphones or an amplified speaker, devices which expect low levels, not directly to a speaker. A speaker output typically drives a 4-16 ohm load (the speaker). If your radio has a headphone output, that would match your car radio input better.

I do not connect my two-way radio to the car radio. I am curious if you hear the whine when the cable is unplugged from your car radio input. What is the impedance at both ends of the connection? Typically speaker level outputs should not be connected to line level inputs. Line outputs or earphone level outputs are better matched.

Encode

It’s true that you can calculate the theoretical losses from that page, but I find it interesting to take forward and reflected power and SWR measurements at both the antenna end of the coax and at the transceiver end of the coax. It allows you to really see the effect of the coax. Your power and SWR measurements at the antenna will more accurately reflect the power that is delivered to the antenna and the true SWR of the antenna. An SWR measurement taken at the transceiver end of the coax is affected greatly by loss of reflected power and doesn’t measure the losses in the coax. So, measure at both places and subtract the forward power at the antenna end from the forward power at the radio end to understand how much power you lose in the coax. Measure SWR at the antenna end to know the actual SWR of the antenna. That’s the place where the forward power entering the antenna and the reflected power from the antenna are most nearly accurate. Best wishes!

I’m not sure if I follow. I’m not going to speculate about the legality without fully understanding what you’re describing. It sounds like you want your friends to use GMRS handheld or mobile radios to talk to an GMRS repeater which is patched to another, more private system of some sort. What is that “more private system?” A diagram would be helpful.

Turn on squelch. It’s purpose is to mute the radio unless certain conditions are met: Carrier squelch mutes the radio unless a threshold signal strength is exceeded.

I’ve used Norton Utilities since Peter Norton owned it and Antivirus since it was released and I’m ready to jump ship. They’ve become the worst at constantly trying to sell a person up. Way more annoying than I want.

And at the Olympics, used by the Chinese ski team.

As a person once said: “I thought I was wrong; it turned out I was mistaken.” Definitely not me.

If it increases enjoyment it might be worth it. Especially for a person who has several of the same $30 HT, or who reprograms a radio frequently, or who wants to import automatically from Repeaterbook, spending $25 for the software might be worthwhile. Or even $49 to obtain a known-good data cable with the software. Good software is sometimes worth the extra price. Just something to consider.

Pin this please!

@WRYC373 - welcome to MyGMRS. I realize you’ve been here a couple weeks now but I didn’t recognize that you were a new member. So, welcome and merry Christmas!

Here’s a thread about linked repeaters:

Maybe it would make sense to start with a non-linked repeater. Many people steer clear of linked repeaters.

Welcome! Great tower and great background! I worked as the JATC apprentice coordinator and later in the control center at an electric and gas utility for many years and our world would have stopped if not for the linemen, electricians, and relay technicians. Anyway, a repeater is connected to the internet with a network node device usually running AllStar software. Most are built around Raspberry Pi’s which have gotten easier to obtain lately. But by no means is it as easy as plug and play. Not that you can’t handle it, but there are always some issues. I haven’t done it myself but I have built some PiStar nodes for ham radio. Based on what I’ve read here the AllStar network nodes may require some source code changes, whereas PiStar is much easier, so my experience is not relevant. Hopefully this helps you a little.

I’m the same way. I don’t off-road just to be off-roading, although it looks fun. I off-road to get from one place to another and I intentionally choose the easiest route for my 4-Runner.

Mostly. It must be on channel 18rp, not just channel 18. But it looks like you have the right DCS codes according to the manual. One thing about DCS codes and CTCSS tones is that you can leave your receive one empty and you’ll receive everything on that frequency. That’s helpful sometimes because you can tell if there’s traffic on the channel.

For all its imperfections, the PL-259 is much more durable than the N connector. That alone might make it worthwhile living with the disadvantages. I have seen the tiny brass fingers on an N female connector broken, presumably because someone attempted to plug in a PL-259. And whoever adopted the same thread diameter and pitch for both should be chastised. I would love to know that history.

@Radioguy7268 I consider your post one of the best posts in this thread. I would only add that, regardless of what your school chooses, you absolutely must train everyone who might possibly ever need to use it and then have them use it frequently (recess duty, sporting events, speech meets, etc.) so in a true emergency its use is second nature. Even though many teachers are often early adopters of technology, some will be intimidated by it and not want to touch it. They’re the ones who will benefit most from training. Also, make sure everyone in a position of responsibility gets training, not just teachers and admin staff. Your classroom helpers, janitors, maintenance engineer, bus drivers, lunchroom workers, coaches, resource officers, etc. It might not hurt to identify some tech savvy students and train them also so they can help if a teacher is incapacitated or distracted by more important details during an emergency. Obviously that’s less likely for younger grades unless you have older students as helpers. I would also make sure someone on the outside gets a radio and training, such as the school board chairperson, county superintendent, or someone with local law enforcement. My wife was a teacher at schools of various sizes from one room, where she was responsible for all eight grades, to a large school where she was one of three second grade teachers. She was always having to send one of the older students to tell another teacher something. The intercoms built into many schools are hampered by the fact that they are permanently installed in the wall. For normal classroom communications they’re barely adequate. In an emergency it’s nearly impossible to whisper and use the intercom. Drill. A lot.

I absolutely agree, but if I ever must change the connector on the radio I’ll put on an N female. M&P advertises that their PL-259 connectors are nearly as good as N males. I haven’t seen test data, but again they’re not cheap.