Leaderboard

Members of the Moderation Staff have noted the 'discussion' - we are leaving things intact as-is (for now) however, we trust that this disagreement or misunderstanding is now resolved and no further outbursts will be placed here. We must all remember that this Forum is made up of persons from all areas of the US and word usage and regional phrases may not be the same in all locations. Let's all be a bit more tolerant and understanding. We are all here to share and to learn and if there are any disagreements, please use the Private Messaging feature here in the Forum to calmly discuss any details that may be unclear between individuals. Thank you for your cooperation.

Please stop mixing up the 1225 family and the CDMs. They are very different radios, but they do have some common features. They both have the 20 pin accessory port in the back and a mic connector on the front panel. On the M1225, the mic connector is an 8 pin RJ45. The CDM mobiles have a 10 pin RJ50. The extra two pins are for a CDM specific DTMF mic. Both families can use the 8 pin RJ45 mics, however, which allows the use of a wide variety of Motorola mics on either radios. Both families of radios program with the same programming cables. I prefer the serial version because it plugs into my Panasonic CF29 Toughbook. I have both aftermarket cables and the Motorola "ribless" serial cable. There is also a USB version of the programming cable, and that will also do both families of radios. And they do plug into the mic connector on both families. The USB cable is not a simple USB to RJ45 cable. There is a USB to TTL serial module in the cable. You are much better off purchasing one that uses the FDTI chip. There are problems with the Prolific chips that can be totally avoided by purchasing FDTI

The M1225 and the CDM750/1250/1550 are completely different families of radios. The M1225 programs fine on Win 7 32 bit or older platforms provided you are using Version 4.0 which is a Windows program. Version 3.2 and older are true RSS and will not run on anything newer than Win98.

All that sounds fine as long as you can be satisfied with around 14 mile radius (or less) from mobile to the repeater, and about 3 miles (or less) radius for an HT. The single, absolutely most important part of a repeater is the effective height of the antenna, the antenna itself, and the lowest loss heliax cable you can afford. After two years of operation, I finally sold my Bridgecom BCR-40U repeater last week. A local GMRS operator put it on his new 150' Rohn 45G tower with a Commscope DB408 ANTENNA UHF406-512MHz 8 bay Repeater Antenna (http://www.va3agv.com/2015/07/commscope-db408-antenna-uhf406-512mhz-8.html for a picture of the antenna). He is also using 1 1/4" LDF6-50 heliax (https://www.awcwire.com/part.aspx?partname=ldf6-50 ) from the antenna to the duplexer. The same equipment on his tower and antenna system now has an effective radius of 45 miles mobile, 12 miles HT. What of world of difference height and antenna made! The tower/antenna/feedline cost ~$5000 The Bridgecom (new) cost ~$1500* *Nota Bene: I sold him mine for $1030. Because he's only about 7 airline miles from me, I still get to use and enjoy the repeater!

I agree with your comment about Digital emissions, the FCC has been pretty clear that GMRS is supposed to be analog voice in a clear & unencrypted state (foreign languages allowed - as long as your ID is in English or CWID). However, when it comes to Part 90, I'm pretty sure that an FB6 private carrier repeater license can be used any way that a paying customer chooses to use it. I've never seen a single action from the FCC since the deregulation in 1980 for "casual communication" on Part 90 frequencies. I've got more than one licensed FB6 (and FB8) system, and I've never cared what a customer talked about. I also don't think the FCC ever asked to look at my books and see how much I was charging those FB6 customers. I think the definition of "Private Carrier" is fairly loose. I just told the Frequency Coordinators that I was planning to offer airtime service to my customers.

You know, it is somewhat amazing to me that Radio people, and the agencies never think about this stuff, and accommodate it. However, a salesman will typically miss it....in my 25 years experience in radio. I think it is simply irresponsible and dangerous for any public safety or public service system to operate without a simplex option. A local (to me) PD and FD went to statewide trunked system a while back, and I am told they have no simplex. The existing VHF and UHF radio (which were in good working order) were zealously ripped out of the cars and trucks in favor of the new "toys"...which work great, but offer no back up to trunked or failsoft repeater operation. I am told they don't even have NPSPAC 800 simplex programmed. Leaving the radios that were narrowband capable (which were most of them) in the vehicles, and using it for back up would have been wise. The FD kept it's VHF repeater and simulcasts dispatches on it, but that's about it. The PD kept their UHF control base....but only to talk to the service department whom they gave the repeater and radios to. They don't even have the ability to use VHF interops from anything they own. 25 years ago every Sheriff's car, PD car, and HP car had VHF with at least 2 common VHF channels and bases all over our state. That was interops. Now they have pretend interops....patching a trunk talk group into another system and fighting with it and the training to get it to work. It's a shame. Sorry that was all off topic.