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Maybe this was my nickname when I first cobbled together two Jobcomm portables with duct tape to make a repeater without using those pesky and expensive filter thingy's back in the 80's....

Do any of you use the TK-880 Radios? I am also considering one. RCM, Are the TK-880's what you talk GMRS on? I am going to go with one of the Kenwoods, as I like their ruggedness. My main activities are Local Emergency Agency (Law Enforcement, Fire Dept, EMS) monitoring & GMRS. Thanks for the comments and help. KipandLee I did reach out to the link you shared. thank you.

Going from 1 watt to 4-5 watts makes a fairly substantial difference (about 10dB more quieting; I'll test it later) when 1 watt is barely understandable, because the signal gets about 6-8dB stronger. Going from 25 to 40 watts is only a 2dB increase, the same as going from 1 watt to 1.6 watts. There are times when that 2dB advantage makes a difference, but it's so rare that it's not really worth it. FM sees a pretty strong rate of SNR improvement with carrier strength increase when it's close to or just above demodulation threshold, but once the signal reaches a good level of quieting there's almost no improvement that can be made using higher transmitter power. [edit] Here's actual, on-air performance between low and high power near threshold.

FB2 is Single User Repeater FB4 is Multiple User, "Community Repeater", Each user group (Ex: Bob's heating and cooling) is licensed for the repeater pair and their mobiles/portables. FB6 is Multiple User, Common Carrier, Only the system (Repeater) is licensed, users are licensed as part of the system when they become users. FB7 Same as FB6 but non-profit FB8 is a trunking repeater (centralized)

We now have four-letter words for people like that.

Yes Mark, the TK-880 is my preferred mobile.

I am going to throw out some ideas for those who are repeater operators. It is an area I am exploring. By now everybody realizes that a 5 watt portable talking through a 50 watt repeater will have its range limited to the ability of that 5 watt portable to "make" the repeater, lets say 8 miles. If that 5 watt portable is talking through the repeater with another user with a 50 watt mobile some 20 miles further distant, that is an inherent accomplishment of the technology. In the public safety arena, UHF 5 watt portables are the critical users. Users want that portable to work everywhere. Public safety seeks to design systems to 97% reliability within a jurisdiction (town/country/statewide). Reliability is the name of the game. A TIA document TSB-88 describes how such systems are designed and tested. For example, if you wish portable coverage throughout a large city or county, the use of satellite voting receivers has long been the solution. Each of these voting receivers has a reliable footprint where a 5 watt portable can be received. Lets say that a small city has three satellite receivers at various locations and where the city boundary is reached, the coverage from any single receiver is 97% reliable. However in other areas within the city, the coverage drops to 70% reliable , if the other two receivers in the system overlap those areas and are also 70% reliable or greater, then > 97.3% "Joint Probability" is attained when the voter switches between strongest signals. For the typical GMRS repeater operator, constructing such a system would require having antenna towers at various locations and a means to bring the signals back to a voter by phone line or other circuit. The towers alone would be costly to build, rent or maintain. However, the hardware, satellite receivers and Voters are readily available on the surplus market and can be pressed into use in a much different way on one site, preferably a rooftop.. All three receivers can be co located on the same tower or rooftop and be used to facilitate multiple receiver diversity reception. Diversity reception can work with two repeaters, but we will use three in this example. If your repeater had 70% reliability out at 8 miles, you could improve the reliability to 97.3% in theory by adding two more receiver antenna branches. To get maximum return, there is a need for the antennas to each receive uncorrelated signals from that distant portable. In a hilly or urban area that may easily be the case. The antennas will have to be physically separated many wavelengths from each other on the tower or rooftop to yield diversity gain. A caveat is that the additional two receivers will need bandpass / notch filters to filter out the transmitter, just as a duplexer would do for a singe receiver station.. I will provide an excel file "Joint probability example" to anyone interested. I was unable to attach it.

I'll just point out that if anyone wants to do UHF DMR, the FCC already allows for that. It's called Part 90 Private Carrier (FB6 designation). Go get a 10-year license - get a Coordinated Frequency pair, and have at it. You no longer need to be concerned about getting Part 95 certified equipment, you don't need to worry about who qualifies as a "Family" member, and you can go ahead and "rent" airtime to anyone you want to, at any price you choose to. There's no requirement to charge a set amount or fee to anyone as a Private Carrier - you get to set your own rates (Zero if you wish), and you get to decide who uses your system. In 10 years' time, DMR will probably be the defacto standard for UHF/VHF conventional systems, but the FCC is slow to recognize trends when it comes to their standards of "interoperability". I think you'll spend a bunch of time herding cats & trying to get everyone to agree on the same type of Digital modulation scheme if you try to get the FCC to make a formal rule change for Part 95 GMRS.

Not to drag this topic further into further CCR bashing there is one important item to consider. The desire to get into radio is something many dont do any more nor have any interest. So the good thing is some people still want to. The issue with the Baofeng or any CCR is the performance as many he mentioned. The performance can impact the users "taste" of the hobby and many times they loose interest cause it doesn't do what it should. I have had this happen in the SAR world and also Amateur world on top of my GMRS repeaters. 90% of the folks that buy those complain they can't hit the repeater or are so broken up and unreadable more folks tell them its junk. This causes them to loose interest and leave the radio world. For me I started grabbing cheap good radios when i have extra cash and leave them sitting. When i get a person who wants to use a baofeng I hand them one of these and let them use it side by side. Normally 2 days later I get "hey can i buy this from you". There is alot of good radios out there dirt cheap that works well for GMRS. I recently picked up 6 HT1000 portables for $50.00. Threw some $20.00 batteries on them and programmed up for GMRS. I have one left in the box. If your truly interested in radio get a reputable radio or your expectations will not be met. JMHO