German amateur radio organization DARC reports on its website a number of novelties found on the HAM RADIO ham fair last week in Friedrichshafen. Most remarkable is the comment on the new Yaesu FT-1D. According to this the new digital Yaesu handy would once again be compatible with Apco P25.

According to our information it is not very probable that this is the case. Reason for the confusion and the lack of info for this might be sensitivities that exist between the different brands acting upon the DV ham market. As the Yaesu FT-1D was first introduced, a year ago at the Tokyo Ham Fair it indeed deemed most likely to be a device according to P25 specifications.

Parent Company of Yaesu, Vertex had it’s divorce from Motorola on January 1st 2012, and that was the exact date Yaesu announced that the new FT-1D is a device that in a first version would be FDMA, so no time slots involved. Later on, a seperate variant of the standard will be introduced, which works with TDMA, i.e. working with two or more time slots.

Speculation was growing then that this was going to be DMR, which is primarily associated with Motorola. Many people associate both DMR and Apco P25 with Motorola. In reality this involves open systems. DMR is standardized under the European ETSI flag, and in the case of Apco P25 the standard was established the auspices of the U.S. government organization APCO (Associatoin of Public Safety Communications Officials-International). In the first years of P25 Motorola was a sole suplier, so everyone thought it was a Motorola system. For DMR, the situation is somewhat similar.

The TDMA variant of DMR hence with the time slots, is indeed frequently hung on as a Motorola system, but there are several other brands producing and selling this equipment including f.i. Hytera.

The time slot-less variant, however, is in particular an ICOM supported system. This system is usually indicated as dPMR, although according to ETSI the system is referred to as “DMR Tier I”. dPMR is also used for the digital version of the popular European PMR446-handies as dPMR446, but it is also for sale with much broader specifications in a regular digital mobile radio version. In particular for the U.S. market next to that there is the NXDN standard, that Kenwood markets as Nexedge, which is marketed by Icom as IDAS. This standard is quite similar to the ETSI dPMR variant, but is not entirely compatible. However, some devices deliverd by ICOM as IDAS can also be delivered according to the European ETSI-rules.

Both dPMR as Apco P25 operate in FDMA, just like this first generation “FT-1D-family”. However ist is not very probable that the FT-1D is based upon a variant of P25, one might wonder how probable an  FT-1D according to the (mostly supported by ICOM) dPMR-rules would be. In the introduction of this new standard Yaesu was indeed particularly harsh about ICOM’s D-STAR system…

©2012, John Piek (QRM! Magazine) – Re-use of this article (unmodified) is permitted under condition that it is attributed bij a link to the original website being www.QRM-magazine.nl