quarterwave

Might be handy for certain situations, maybe even a travel repeater...at 4w if you use a good antenna and keep the line short at least you could double your range. I can see strapping one to the balcony of the beach house! Most of this stuff is so china-cheap...and a gamble if it works. I'd be interested in the price.

https://anytonetech.com/ Full line up.

Not exactly about linking, but I was trolling the eBay the other day and a guy was selling a "GMRS cross band repeater". He had 2 M120 (a UHF and a VHF) Motorola mobiles, a home brew criss cross cable, and was showing how to make it work with a Chinese radio which was showing 462.xxx and 146.xxx. I wanted to send him a question on his listing asking if he knew that was illegal...but I get tired of fussing. He knows, I'll put money on it. Of course, it's not illegal until he/someone transmits.

I noticed that too...no rhyme or reason in the programming...like they just threw something at the wall and it stuck. The GMRS version I saw had MURS in it too, but it pretty much looked like anyone with any knowledge would want to reprogram it.

It's always been "allowed" so to speak, there just hasn't been an "allowed", feasible way to do it. Interconnection to PSTN refers to "telephone interconnects" or "patches" which run through switched telephone services, as in it has to be dialed to connect. Use of leased lines to remote to, or connect repeaters has always been "legal" but you won't find operators who want to pay good money for a leased line just to connect GMRS repeaters. In-band linking isn't ideal, not enough seperation, so that leaves voip, which, as mentioned, wasn't even around when these rules were written.

When I started in radio an older tech said the only difference in a 1/4 wave and gain antennae was the price. I have never gone wrong with a good old 1/4 wave on any of my UHF equipment. I used a 1/4 wave Vhf as a scanner antenna for years. The only time I had any better service out of a gain antenna was when I had a BC780 scanner in my work van. It had a ladder rack on it, and a UHF Motorola Spectrum (about 20 year old vintage) out shined the 1/4 VHF for both VHF and UHF reception, and 800 was about the same.

Yeah, that RS unit was neat...surprised no one else has tried it. It's still a unicorn on eBay...just happened to see one once.

Here is the thread from RR.com...so I don't reinvent the wheel... http://forums.radioreference.com/gmrs-frs/305669-cool-little-gmrs-mobile-introduced-midland-ces-2015-a.html

I thought it may be because public safety, etc is public information, HAM is an open "hobby", but GMRS and likewise a "business" repeater or base, are more of a private deal. Not private in a "protected" sense or under some guise of privacy from listeners, but the type of communication is really not in the spirit of "action" most scanner peeps are after.

I like the looks of the TERA unit on the site now, keypad model. I have checked their site before, they seem to be carrying more and more radio gear. I like it!

I won't disagree with most of that, however being a M employee in the hay day of those mobiles, you may be surprised at their hardiness. Yes, while they are certainly not a MSF5000, they make decent little repeaters. For HAM use? No, HAMs like to TALK! You need a 100% duty cycle repeater for that, but for GMRS, or even light duty commercial, they can and do work. I ran a 40 watt M120 as my GMRS repeater TX for 16 years and never had to touch it. When I did remove it and replace the cabinet with a MTR2000, that M120 was on freq, had a good RX even though that wasn't really being used, and keyed to 41 watts, dropping to about 37 after 2 minutes. Now, I am not saying it would do that continuously, but for the sporadic conversations we had on the repeater, it was fine. Never had an issue. I had TOT set for 3 minutes with a re-key time, so people knew to give it a rest, and I mounted it with the heat sink up at the top of the cabinet with 2 - 4 inch fans right above it and controlled air flow in the front and over the radio. The RX was a M208, and it still works great too, as a receiver on my secondary repeater. The later M120/GM300/Maxtrac series had power cut back, so unlike the older M100/M2xx/Maxtracs, you didn't have to set the power back on a 40 watt to say 25, or a 25 to 10 to keep from frying it easily. The Maxtrac series PA was also used in Desktrac bases and repeaters. So yes, these are not meant to be heavy duty repeaters, but for some GMRS guys, they make good ones, and can be the difference in spending a few hundred dollars and a few thousand with no better results. I wouldn't scare anyone off from using them, especially in a first time project.

I figure it's like the GMRS rules, where we, the licensees mainly keep the hobby in check. With MURS, no one going to even know how or that they should complain....not many people could/would even realize someone is using 5 watts versus 2, and probably wouldn't care anyway. Can't imagine the FCC caring at all, since they don't tend to want to keep FRS-ers off of GMRS for us. I'm in a semi rural area, used to hear more on .600 and .570 than I do now. I think alot of drive through's have switched to digital systems, seemed to be alot of them using these freqs in years past. I know that one business around here used to have .600 in their 45 watt mobiles. When they converted to narrow for the rest of their system, .600 came out of the programming and a newly licensed itinerant went in it's place, so they are legal now. They never had a license for .600 anyway, my source said they started using it in portables many years ago to coordinate with a contractor and just never stopped...ended up in mobiles...and through changing people overseeing radio for them, the upkeep and legalities got lost in the shuffle. They are square now, but it just shows how things get forgotten about and companies end up getting fined...all because people changed jobs, left, ball got dropped, no one paying attention. And for every one that gets fixed, there is probably 10 more not. I worked for a radio shop years ago, so I learned the right way.....follow the rules, and it's no one's fault but your own if you don't.

I didn't do much research, but thought I would ask aloud, with the MURS rules for 2 watts, I wonder how many licensed and non licensed radios are being used on .570 and .600 at wideband and 5 watts simply because they were grandfathered on the freqs.

I've operated a repeater for many years, but never publicized it because it was mostly family and we didn't want anyone else in the mix. I paid for it, so I get to say. In our area there are few to no real GMRS operators besides me/friends except for the occasional bubble packer that wanders on to the freq I use, of course we run DPL so we don't hear them. With that said, I do have an "open" repeater. I put up a lower powered unit on a different freq at the same site. I have it listed, and I too say open to all licensed users, follow all rules. It's doesn't ID on it's own, so it's up to them to use it right and ID. Not sure I have ever heard anyone use it. I do know a local rental yard runs simplex (illegally) on that freq and they don't like it when I am testing. LOL. In area's of heavy use, I can see why people don't want to share an expensive repeater they want to use for them and their buddies. Nothing says they have to. But, I do think that if you have the means (a small repeater made from 2 mobiles is cheap) and there are lots of people using, put up a public machine too. As far as HAM goes, I know anyone can use the local (to me) clubs repeaters, but you are encouraged to join if you want to gab all the time. Back in the day, you had to join to get a DTMF code to use the autopatch.

Yeah...GMRS has access to the lower side offsets at full power (4 watts), FRS can only use them with 1/2 watt. FRS is exclusive use only on the upper side 467 offsets at 1/2 watt. Been that way a long time. I have used 462.6125 and 462.6375 as my channel 3 & 4 for simplex in my Motorola's for years, repeater and T/A in 1 & 2.

I'm not sure it was ever specifically mentioned in the GMRS rules, either allowed or not allowed. 6GHz microwave is used for all kinds of stuff. I don't see why a person could not use it to link a couple of stations, but I think it centers on channels, and the finite number of them. Is it necessary, and does it limit others ability to share the channels (if you have a 650 tied to a 700 in two adjacent locations, maybe 10 miles apart or even the same channel and further apart used just for creating more "coverage" for a unified system). Probably just comes back to common sense. Lots of dreamy projects out there, but practical and necessary is another story. 6 GHz microwave hop and the license will cost a few bucks.

Great points to reiterate. I have talked to people about these time and time again. People that know enough about radio to be dangerous often think more power is better. but with these repeaters, location is everything. If your portable radio is 4 watts and the antenna height is about 5 feet when transmitting, and you can make the repeater just fine...then your repeater only really needs 4 watts at the antenna to get back to you the same. Of course, there can be other factors, but this is why those little 12w UHF industrial repeaters always worked well at manufacturing plants, you put them on the smokestack or the water tower, etc...and you had all the range you needed for the job at hand. When I worked for M we had a big plant that had 6 or 7, 25 watt UHF repeaters going....set it and forget it. I don't think we ever went back for anything on those until we moved them once. On a wider scale, we had a volunteer fire system with the "100 Watt or die" mentality. Over the years they had gotten more and more portables until that was the primary radio, and the mobiles they now had were 45 watt dash mounts. The repeater was at an awesome site, so we had their repeater set for about 50 watts, and you could always hear it at around 20 miles further than they could talk in...but that was ok, no need to talk in on a portable from 2 counties over! They never knew it wasn't running at 100 watts, they couldn't tell. The worst case of this not being heeded was a manufacturing plant on about 300 acres...with 6 VHF repeaters, and antennae on the roof (about 40 feet off the ground) and among various exhaust stack, piping, railings, AC units, etc....all things that deflect and attenuate signals. They had a "guy" that insisted on big power. Well, with 6 VHF repeaters running constantly during the busy day, that place, and a 1/2 mile around it, is a giant intermod factory! They recently narrow banded, of course, and I was told they dropped the power to 50 at the base except one repeater that's at 75-80 because the head Maintenance guy wants to hear it at his house 20 miles away....boo hoo...I'm sure this place provides him a cell phone. I heard they were advised to reduce the power...not sure if it was for the intermod issue, or the FCC reduced their power. Either way....that's up to 12 VHF frequencies on the air at once! I would venture to say 10-15 watts would work just fine on those repeaters. After all the years, still can't see why they are on VHF at all...but this point, they should be on a UHF or 800 trunk, which could be put on a on-site tower and be easier to service, etc. Oh well, not my money.

The shop I worked for put in 2 UHF repeaters in high profile locations on opposite ends of a large county for a water utility some years ago. They wanted coverage everywhere...the mobiles were 100 watt Maratracs. They used no portables, with the exception of a supervisor or two that had a PacRT with a 1 watt VHF portable so he had coverage out of the truck. The base did not want to switch frequencies. Ever. But they wanted to hear both repeaters, and have mobiles on one repeater hear the other, and vice versa. They got some waiver on the license to make this happen, there was a letter from the FCC at the time, I had seen it. The frequencies were exclusive for 150 miles and one pair was 450's the other 460's. So to accomplish it, they put a link radio at 4-5 watts with a yagi on each repeater site, pointing at the other. When one was being used, it keyed it's link radio with same audio on the input of the other repeater (not a link frequency). Trucks could be on either repeater and talk, no channel changes needed. They just ran on what ever channel worked in their area. Base stayed on one channel...but we did put the other in it just in case of failure. They did not have talkaround at all at first, but I think later on, the shop added it for one frequency.

I have seen those, doesn't look hard to do. One of the contacts goes straight through the battery. I do know there are some chargers with 3 pins, and some with 4, essentially one is missing on the 3 pin. I have like 12-13, I should look at them.

I have tried alot of them....HT600, P100, P200, HT1000, MT1000, P110, GP300, P1225, Visar. A good HT600 was hard to beat...and I like the P1225 most. I was assigned a new Gp300 when I worked for M. 8F later converted to 16F...UHF as we used M Community repeaters all over the place. I still have it!

I like the M1225 and P1225...I have a couple of each. I also have a new 4F M1225...in the box! Most of my mobiles are older, but work reliably. Most of them are in Farm equipment. What I am working towards with my system is eventually making it a primarily handheld system. The coverage I have is fine, if I can improve it, I will, but with the cost of equipment and they way I use it outside of some farm coordination now and then, just doesn't warrant needing mobiles. I will keep one for my pickup truck, but other than that I want to focus on a portable radio coverage system...just like cell phone use...more of a carried device than a fixed, or fixed in a vehicle thing.

Yes, once you find your way around M equipment, like I did working for them in the early 90's, its is cool to see what you can get into. Our shop built alot of interesting things back then. I run a pair of M208's as a small repeater, I have it set for about 15 watts, and it works just fine. Celwave mobile duplexer and a MRE1032 RA_1 interface. I used the interface to get the audio adjustment and drop out delay. I also keep a couple of my own cables around to make a quick repeater if I have to. My main machine is a 100 watt 100% duty cycle MTR2000 turned down to 50 watts....with a Zetron 37. Love that thing.

Appreciate the counter points. I wasn't suggesting the R100 was not a good unit, it was good for what it was built for, which was not to be a 100% duty cycle heavy duty repeater. We sold alot of them when I worked for M, and they generally were great. I did see some melted down because the customer needed a MSR2000 or MSF but didn't want to spend the money. I would hate to see someone buy one that may essentially be salvage, and may not be working....but buying one from a seller that can test, and would take it back if it wasn't what he said it was, would be better. Especially if you are are just-getting-started radio guy. I would disagree a bit on the Radius and Maxtrac....I have seen many a small repeater made from them, and they are a reliable, well made mobile. I have some that are 20+ years old and work just like new. I do understand that everyone's experience will vary, we each like what we like.

If no duplexer, then yes, you must have vertical and/or horizontal antenna separation. Not always easy to do, or do right. That R100 looks ok, but you never know if it works and for how long, I am always wary of a reseller like that ("I bought it from XXX or an auction....was in service, untested, not tested, etc.") It is usually best to buy from someone who can test it (beyond plugging it in!) and at least for frequency, power out, and audio, which doesn't require a radio shop if a guy knows what he is doing. Also, on something as old as a R100 (they started making those in the late 80's and stopped in the early 90's) you want to be sure someone can program it. It takes a cable (or cable and RIB) and a PC that can run DOS, as well as a copy of the R100 software. So, not to discourage anyone from buying an R100, but I don't want anyone to buy a boat anchor either. Sometimes you can find repeaters on eBay that guy's build them selves, and while they might not be able to warrant the equipment, at least the put it together and generally had some means of testing it. If worse comes to worse, a simple controller from MRE1032 like http://www.ebay.com/itm/RA-1-Repeater-Adaptor-Motorola-GM300-CDM-1250-RICK-/350465888363 and then a couple of M120, Gm300, Motorola Radius or Maxtrac radios with 16 pin connectors will work fine. I have one of those I built right now. All you need is a mobile duplexer off Ebay and then get the radios programmed and the duplexer tuned and you are ready to roll.

Welcome. If you are still talking about a simplex repeater (simplexer, parrott, etc) you don't need to separate the antennae at all, since neither receives and transmits at the same time, and in the case of a simplex setup...you would only need 1 radio, as it is store and forward. These projects are cool, a guy has to touch and see this stuff, get a feel for how it really works. I would ask what the terrain is, seems like 180 acres would be easy to cover with just portables and no repeater. I have used them on my family farm for years. The down side of the simplex repeater setup like that is durability. The TX radio is working twice as hard, carrying transmissions from both sides of the conversation, plus you have to wait for your message to repeat, and then the other guy talks, and his repeats. Make for a slow conversation. They have their uses, so it's not all bad. I made a "heavy duty" one once using a 40 watt mobile, a PC, custom interface, and Echo Station software. Still have the parts, but don't use it any more. If coverage is the real issue, I would lean towards a 10-25 watt repeater with a duplexer. It's just cleaner, easier and more reliable in the long run. But, by all means, if you have the means and desire to "tinker" like most of us, don't be discouraged from building a simplex machine, best way to learn is try, and try again.