Regarding the Mars Cap Mod on the Yaesu FTM-150R, does that mod open up the GMRS frequency range for Transmit (TX)? If so, does transmitting on that range void any warranty, either from the Manufacturer or the GigaParts 10-year extended warranty - assuming I have an antenna for GMRS?
The MARS mod for the FTM-150R removes the TX band edge limits. Technically, the radio will transmit on GMRS frequencies after the mod is performed, but doing so would be illegal. Regarding warranties: the mod itself does not void any warranties, but if you burn out the finals, for example, by transmitting on a frequency that the radio and/or its antenna system is not tuned for, that damage is not covered under the manufacture’s warranty or the GigaParts 10-year extended warranty. Transmitting outside the frequency range a radio was designed for can cause the radio to generate additional heat internally, shortening the life of several internal components.
Understood. Assuming I have an antenna matched for GMRS, after the Mars Mod, is the radio then technically, to use your wording, “tuned” for GMRS?
Not necessarily. There are adjustments made by the factory to tune the radio. Even with an antenna system that is resonant on GMRS frequencies, a radio not designed or tuned to transmit that far out of the ham bands would eventually have components fail, especially if transmitting on high power.
just purchased new icom 2730A from GP, paid for mars cap, when you go to air band 118-136, its stuck on am band, cant change it and will not tx in that band, radio looks like its never been opened… am wondering if someone missed the mod or?? pls advise thanks
The IC-2730A changes to AM on 118-136 because that’s typically the mode aircraft radios use on those frequencies. There are not many ham radios that can transmit on those frequencies after a MARS mod, and even fewer that can transmit on AM. The original Yaesu VX-7R is the only one that comes to mind.
If the radio will transmit in the 150MHz range, you can confirm the MARS mod has been completed.
All good on the tx on AM, am thinking it should tx w the cap mod especially being used for use on aircraft band… the 2730A just wont tx on that band as well…radio is new, purchased 2 weeks ago, ill check again, also is Icom software possibly needed to make this effective on this radio w the mod? Ill check on TX in 150 band Thanks!!!
Technically, there are no CAP mods anymore. CAP uses P25 and the NTIA requires radios used for CAP be certified and appear on their list of approved radios.
I’m pretty sure the Icom software would not make a difference. I think 118-136 is just way to far from what this radio’s transmitter was designed for.
good to know, the band isn’t that far off from 2 meter, if giga is offering the mod, for that model it should simply work correct??? my goal is to simply have all capabilities we need in one decent radio…hence the mod, if theres a diff radio,besides the vxr you recommend im standing by .Thx!
The mod simply removes the edge limits for the ham bands, but there is another set of edge limits that remain in place that have more to do with the physical limitations of the radio. The bigger issue is that the IC-2730’s transmitter is not capable of transmitting on AM, which would be essential for communicating on the aircraft band. And then there’s the regulatory hurdles.
There are a few commercial radios, like the Technisonic TDFM-9000, that are capable of, and certified for, transmitting on the aircraft band, the ham bands, and land mobile frequencies. They’re commonly used in police helicopters but are very expensive…like north of $50,000.