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Yes, you may cut the cable and solder it to a new mount. Yes, you may reduce the length of the cable to suit your needs. You merely need to make sure are properly terminated and the end of the coax is adequately protected from moisture ingress. Michael WRHS965 KE8PLM Sent from my iPad using Tapatalk

Just, FYI, FCC compliance is binary, You either have it, or you don’t. I.e. there is no partial compliance.

It is possible that the repeaters you are trying to access no longer exist or have outdated contact information. I receive emails now and then from people wishing to use the linked repeater so I do know the emails are going out.

You're getting those static if you're on the edge of repeater's coverage range if you're in the correct repeater frequency you will having any problem hearing your transmission to your other radio. and on the positive note don't worry if you miss up something its all about learning, experimenting and having fun!.

I've noticed that, too. It just seems to me that it makes more sense to find a repeater nearby. And if there ain't one nearby, well then tough turds or try to find local traffic on your radio's own power and go from there. Personally, to me, making your own repeater station is a major PITA if you're not knee-deep into this hobby with deep-ish pockets. Just my $.02. Scott WRJX210

I believe the FCC addressed this in: §95.1761 GMRS transmitter certification. © ... No GMRS transmitter will be certified for use in the GMRS if it is equipped with the capabilities to operate in services that do not require equipment certification, such as the Amateur Radio Service. Huh... Doesn't seem to get any plainer that that, I guess.... LoL

Found a function on the MXT400 the other day that I didn't see in the manual. You can scan for CTCSS or DCS on a channel if you long hold the CTCSS/DCS button. The codes will start scrolling. If there are active communications on that channel, it will eventually pause on the code. I've use it on the repeater channels to help figure out repeater tones if there's chatter.

Well, my recommendation goes to a 2nd hand (used, but not abused) Motorola XPR4550 mobile. These XPR4550 are very nice, and they can be found in decent condition for around 100-150 bucks on the bay, cable can be had for 20 bucks, and the legacy CPS can be purchased on eBay as well. These mobiles have a proper superhet receiver with a multiple tuned varactor front end, which will allow you reach more than 2 miles on a lot less power than 50W. To give you an idea, my XPR6550 portable, (which uses the same receiver as the 4550 mobile) can easily reach 1.5 miles on just 1 watt. Where? in the Madison WI area, which is super-hilly suburban terrain... All my 6550 radios are used (2nd hand), some have small scratches, etc, but the scratches didn't stop them from demolishing all the crap inexpensive radios I own... Some background: most of those GMRS cheap mobiles usually show a 10-20 dBm loss in effective sensitivity, a loss that cannot be made up by just cranking power to 50W. 20dBm means you'll need 100 times the power to make up for it... So, if a radio has 95 dBm effective sensitivity means that it won't be able to hear anything below the 95 dBm mark... vs. a radio which has 115 dBm effective sensitivity, which will be able to hear equally good a signal coming from a 1 watt radio as a 95 dBm effective sensitivity radio would hear a 100 watt signal. That is the importance of having a real receiver with tuned front end... etc. G.

About a -10dBm difference at equal distance in free space, 145 vs 460 MHz, but then you can also have much higher gain antennas for equivalent lengths, so in the end its mostly a wash... provided you setup things right, emphasis in "setup things right". G.

Simple question, complex answer. From a radio perspective, it is completely compatible. That means you could transmit on that radio, and be heard on a GMRS radio, and vice versa. However, that radio is not specifically approved for use on GMRS. How you feel about using a non-approved radio is up to you. I will not go into that discussion here because it has been covered many times on this forum.

I have built more than one repeater from a couple of Motorola Radius or Maxtrac mobiles. The best cables I have found are from MRE1032 on ebay. The simple one has audio level control and optional delay. I have made my own cable also, it's easy. I actually used a couple of Maxtrac's and a cable I made up in 10 minutes back about 20 years ago when I was working for M and our local city service departments' GE VHF repeater went kaboom on a summer day. Hooked the mobiles up to their duplexer, and made them a temporary 20 watt repeater. They actually wanted to keep it...I think it worked better than the old GE. I have seen the old "Industrial" MSF5000 repeaters...big cabinet, all the regular heavy duty internals...and a 6 watt PA.

I looked at building some out of TK880's but I couldn't find the little pigtail anywhere (I guess Kenwood's version of the OPC-617 that my Icom's use). 16 pin Moto's are easy, $10 cable from China, programming the pinouts and you are GTG (minus the duplexer/antenna setup). It's very rare to see low duty repeaters in commercial operation that aren't based off of mobile radios. Especially in applications where a desktop unit isn't needed (GE MASTR II and Kenwood TKR desktop units). The Icom CY-series of repeaters are mobile based as are the GR series from Motorola (GR1225 excluded), think I've even seen a GR style from Moto based off the CDM line. Two mobiles can be put together to form a repeater. In some cases with older (crystal controlled) mobiles, you can actually make the receiver and transmitter run full duplex and convert a mobile to a repeater. Examples of this are Motorola Micor, GE MASTR II, Motorola Mietrek…

Since this topic is so labeled as Repeater Building 101 I figured this would be a good place to place this post as it relates to repeater building. I have recently obtained an RF Signal Generator as well as a Spectrum Analyzer for radio work. I am able to do duplexer tuning with this equipment. If anyone needs duplexers tuned PM me and we can work out the shipping and tuning details.