SteveShannon

I agree with KAF6045; make sure you know how to sweep the antenna first and that you see something that makes sense to you. Then sweep the antenna using the other port on the analyzer to make sure you're seeing the same results on both. Only after you have confidence in the analyzer and your ability to analyze an antenna will you feel comfortable performing a two port analysis of a filter or one side of the duplexer.

The most common type of PL tone is also called CTCSS. There’s also DCS To determine it you ask a repeater owner or you can scan for it with some devices.

I was project manager and programmer on an Intergraph FRAMME system between 1999 and 2005. Ours was PC based but I spent many hours working with folks in Huntsville that you might have known.

I see what you did there … ?

I don’t know if you watched these videos but Randy (@OffroaderX) discusses some of these things:

@OffroaderX discusses the desense issue in one of the (Notarubicon) videos he did about building a KG1000G based repeater.

It looks like you posted this question in two different places. I responded in the other.

They probably cannot be that close together. The receiver will desense. Also, how are you separating the transmitter signal from the receiver signal? Are you using two different antennas or a duplexer? If two antennas how much separation do you have?

The 2 meter repeater here probably has one or two conversations that last a few minutes each day, until our club holds a net each week, when it has to transmit for 15 to 20 minutes nearly continuously. So except during that time duty cycle is not crucial, but it it weren’t able to transmit continuously at least 20 minutes it wouldn’t be useful for emergencies. For a family repeater I agree with you, it’ll be very short transmissions with lots of cooling in between. For that matter, with the KG1000 radios, if you burn out the transmitter just swap them and make the one with the pristine transmitter the new replacement. Or you could always run it at medium power. You might never have a problem with less power running through it. I’ll be really interested in what you decide to do. For my rocket club I have plans to pick up an RT97s. We would use it one day per month for eight months of the year and probably only ten minutes total each of those days. I’ll simply ask my members to say my call sign every so often to ID the repeater. The only reason to have it is to allow people looking in gullies to be able to radio back to base.

Honestly I wouldn’t even worry about the duty cycle. I’m sure in some places repeaters get a lot of use, but most of the ones I hear in Montana are seldom transmitting more than twenty minutes continuously. Run it until it needs to be replaced, then you’ll have a pretty good idea.

You’ve got it! Best wishes getting that set up!

I didn't vote. I'm not one to put stickers on my vehicles, though and I really don't drive around with my radio on. I only use my GMRS radio when my kids are at our cabin or when I'm launching rockets with friends. I don't use GMRS the way I use ham radio, where I might sit at the radio an try to listen to distant stations or join in a local net. For me, although I'm interested in the technology and regulations, GMRS is just a way to communicate while enjoying other things.

It can be as simple as instructing anyone who uses your repeater to identify it whenever they identify their own stations, but of course that's subject to human frailty. For example, if I were using your repeater, I would say "This is WROM258 on repeater WRMM689." Some (most) people purchase a device called an ID-o-matic, that sits between the two linked KG-1000G boxes and which automatically follows the rules for station identification. The Retevis RT97 doesn't have an easy way to insert an ID-o-matic. Its newer version, the RT97S has a port that should allow the use of the ID-o-matic, but I haven't done it so I cannot comment on whether it's easy or difficult. The RT97S used to be much more expensive than the RT97, but lately they appear to be very close in price. In fact, the shopping portal associated with this site had the RT97S for $100 off just the other day, but I think it was a limited time offer. Edited to add: And there's at least one repeater owner who simply setup a Baofeng attached to his/her computer which transmits a call sign to the repeater every fifteen minutes: Here are the FCC rules for GMRS identification: § 95.1751 GMRS station identification. Each GMRS station must be identified by transmission of its FCC-assigned call sign at the end of transmissions and at periodic intervals during transmissions except as provided in paragraph (c) of this section. A unit number may be included after the call sign in the identification. (a) The GMRS station call sign must be transmitted: (1) Following a single transmission or a series of transmissions; and, (2) After 15 minutes and at least once every 15 minutes thereafter during a series of transmissions lasting more than 15 minutes. (b) The call sign must be transmitted using voice in the English language or international Morse code telegraphy using an audible tone. (c) Any GMRS repeater station is not required to transmit station identification if: (1) It retransmits only communications from GMRS stations operating under authority of the individual license under which it operates; and, (2) The GMRS stations whose communications are retransmitted are properly identified in accordance with this section.

It's true that a repeater must be IDed if either or both of those two clauses is not true, but there's no technical requirement for an automatic ID system. If the operator and users of the system identify it according to the rules that is sufficient. Of course from a practical standpoint having an ID system is much more convenient.

I sense a video from Notarubicon … I look forward to seeing it.

Good for you! That and a belt clip will really do the trick with the ladies! ? Honestly I suspect that’s not your call sign and you’re trolling someone here, but that’s your business as well. Yup, your call sign is wrbu527. I’m sorry to be right.

Here’s one of the posts where WRFP399 describes his RT97S setup. I’ve always been impressed by it: Steve

Yes, I think it’ll be the gentleman in Alaska. Wrrc399 or something like that. I’ll look for it.

Welcome, Rodrigo! Without truly knowing what you consider “low-priced” I will say that the easiest path is probably to just buy a Retevis RT97, a good antenna, the best coax you can afford, and a mast to get the antenna up into the air.

Not really. Marc and I both answered his original question. Then, like conversations sometimes go, Gortex2 introduced an inflection point. Almost all of us understand that the conversation that’s going on now has almost nothing to do with the OP’s question. That’s just life online. It has been an interesting diversion though.

I googled “emergency protocols for FRS radio” and I’m delighted that I found many sites and documents that describe such plans. Unfortunately they are dissimilar, but for people in those areas they may be very useful.

Yes, I think that’s crucial. Here’s something else:

Certainly it’s not ideal, but for $200 I could donate 10 Baofeng radios and set them up to scan all the GMRS/FRS radios and all the local ham repeaters and probably the SAR frequencies as well. These could be provided to folks who are out searching for a lost person. I agree; there’s no perfect scenario, but as long as people are willing to keep working towards solutions, some things will improve.

So again, we need to be taking a more proactive position in teaching folks who travel into the woods how to be prepared to use their radios (and what kind of radio to have, and identifying an emergency channel, etc.) Putting ourselves in the position of Joe Schmoe: You said you take your ham radio if you don’t have SAR coverage, but both of those choices that you have are out of reach of the average person. How does the average citizen (who isn’t part of SAR) get SAR coverage? You have options that are unavailable to most Joe Schmoes. For this discussion you need to look at things from their perspective. Also, most people going into the woods don’t get ham radio licenses. But they do buy the bubble pack radios at the sporting goods store. They’re right there next to the guns and ammo. You know the old saying that “You go into battle with the army you have, not the army you want.” This is the same thing. People are going to buy and carry bubble pack radios. SAR needs to be equipped to deal with that reality. And once SAR is equipped to deal with that then it makes sense to use GMRS. SAR cannot monitor every tone and channel? That seems like something they might want to do. A good scanner would certainly enable them to monitor all the GMRS channels and they don’t need to monitor all the different tones; just leave them all clear. Of course they might need to be able to transmit a tone in case the lost soul has implemented a tone squelch in his/her receiver, but scanners reveal tones as well. All of us, before going into the woods, should identify which band and frequency SAR is likely to listen on and be ready to use that if needed. This is where you need to acknowledge that the person you’re looking for is more likely to have bubble pack radios than anything else and adjust to that reality. SAR groups should work with fish and game, USFS, BLM, etc. to advertise how to get help (and maybe they do - but it’s not immediately obvious in my area.)

So what do you carry when you’re simply Joe Schmoe going for a walk in the woods? Most people have nothing other than a cell phone. A GMRS radio or ham radio is a step up. People who go out in the back country professionally carry PLBs, but very few recreational hikers do. It’s better for people to carry a GMRS radio that they know how to use than to leave it at home because someone on the internet said “I would never trust a GMRS system with my life.” I agree with you on this: if I knew I was going to be going into a situation that required reliable communications, I wouldn’t choose GMRS as my first or even second choice. I’d insist on a PLB and probably a satellite phone. But we should be encouraging recreational hikers to carry some kind of communications gear and we should be advising them so they can make informed decisions.