I am thinking of acquiring a couple of the Jackson Labs M12M replacement receivers to use with my RTCM units. It appears that they might greatly simplify the process obtaining a GPS derived 1 PPS signal, especially for temporary / portable repeaters that require voting receivers. They are currently available for under $200 per unit, shipped. http://www.jackson-labs.com/assets/uploads/main/M12M_replacement_Specsheet.p... http://www.jackson-labs.com/assets/uploads/main/M12M_replacement_UserManual.... These were designed as a retrofit for a specific earlier GPS receiver but they appear to be potentially useful to supply at least the 1 PPS signal required by the RTCM. They might also act as a frequency standard for simulcast, although they may not have the oscillator required to provide a stable frequency source in the event of loss of GPS signal. Does it appear that these units would work? Has anyone experimented with this or similar units with the RTCM? Thanks. KE6CD