The Digital Voice Committee recognizes that there are several digital voice formats available for use on the VHF and UHF bands

Adopted by T-MARC Membership on 2/22/09

Digital Voice Frequency Coordination Plan

The Digital Voice Committee recognizes that there are several digital voice formats available for use on the VHF and UHF bands. Some of these formats, such as D-Star, are of a narrow bandwidth. Others are typical of the bandwidth of a normal FM signal although the information is in a digital format. Therefore coordination of Digital Voice systems is dependent on the bandwidth of the signal rather than the fact that a digital voice mode is being used. Modes, such as D-Star, with a FCC Occupied Bandwidth not exceeding 6.25 kHz shall be considered narrow band (NB) for T-MARC coordination purposes.

Presently Digital Voice repeater systems operating in the 2 meter repeater sub-bands that use D-Star or other narrow band emissions are being coordinated on the “split” or interleaved channels of the 2 meter repeater sub-band where the typical channel separation is 20 kHz. The typical FM repeater frequencies being separated by 20 kHz, places these systems 10 kHz from the adjacent frequencies presently being coordinated for analog FM repeater systems. These repeater frequencies are between 144.50 and 145.50 MHz and are shown in Table 1 below. Geographic separation similar to that presently considered will be utilized between new narrow band repeater systems and the analog repeater systems on the adjacent channels. Similarly, geographic separation between co-channel narrow band systems will be considered. This policy is consistent with the SERA band plan to the south of the T-MARC coordination area and was adopted by the T-MARC membership at the last annual meeting. Coordination bodies to the north have not made a determination that they are prepared to announce. Digital Voice repeater systems using other formats that are not defined as narrow band will be coordinated on the frequencies typical of analog FM repeaters.

Input	Output	Mode	Input	Output	Mode
144.51	145.11		144.71	145.31
144.52	145.12	NB	144.72	145.32	NB
144.53	145.13		144.73	145.33
144.54	145.14	NB	144.74	145.34	NB
144.55	145.15		144.75	145.35
144.56	145.16	Not Used	144.76	145.36	NB
144.57	145.17	SNP	144.77	145.37
144.58	145.18	Not Used	144.78	145.38	NB
144.59	145.19		144.79	145.39
144.60	145.20	NB	144.80	145.40	NB
144.61	145.21		144.81	145.41
144.62	145.22	NB	144.82	145.42	NB
144.63	145.23		144.83	145.43
144.64	145.24	NB	144.84	145.44	NB
144.65	145.25		144.85	145.45
144.66	145.26	NB	144.86	145.46	NB
144.67	145.27		144.87	145.47
144.68	145.28	NB	144.88	145.48	NB
144.69	145.29		144.89	145.49
144.70	145.30	NB

Table 1

Digital Voice repeater systems using D-Star or other narrow band emissions and operating in the 70 cm band are being coordinated on the “split” or interleaved channels between the typical FM repeater frequencies. Table II below provides an example of how the narrow band (NB) frequencies are to be interleaved between present repeater input and output frequencies. Although this table only covers 1 MHz of the band, this represents the typical frequency relationship utilized throughout the remainder of the band. The typical FM repeater frequencies, at 25 kHz intervals, are to be interleaved by the frequencies assigned for narrow band systems. This offers 12.5 kHz separation from the adjacent channel. Geographic separation similar to that presently considered will be utilized between new narrow band repeater systems and the analog repeater systems on the adjacent channels. Similarly, geographic separation between co-channel narrow band systems will be considered. This policy is consistent with the SERA band plan to the south of the T-MARC coordination area and was adopted by the T-MARC membership at the last annual meeting. Coordination bodies to the north have not made a determination that they are prepared to announce. Digital Voice repeater systems using other formats that are not defined as narrow band are being coordinated on the frequencies typical of analog FM repeaters.

442.0000	OUTPUT	442.2500	OUTPUT	442.5000	OUTPUT	442.7500	OUTPUT
442.0125	NB	442.2625	NB	442.5125	NB	442.7625	NB
442.0250	INPUT	442.2750	INPUT	442.5250	INPUT	442.7750	INPUT
442.0375	NB	442.2875	NB	442.5375	NB	442.7875	NB
442.0500	OUTPUT	442.3000	OUTPUT	442.5500	OUTPUT	442.8000	OUTPUT
442.0625	NB	442.3125	NB	442.5625	NB	442.8125	NB
442.0750	INPUT	442.3250	INPUT	442.5750	INPUT	442.8250	INPUT
442.0875	NB	442.3375	NB	442.5875	NB	442.8375	NB
442.1000	OUTPUT	442.3500	OUTPUT	442.6000	OUTPUT	442.8500	OUTPUT
442.1125	NB	442.3625	NB	442.6125	NB	442.8625	NB
442.1250	INPUT	442.3750	INPUT	442.6250	INPUT	442.8750	INPUT
442.1375	NB	442.3875	NB	442.6375	NB	442.8875	NB
442.1500	OUTPUT	442.4000	OUTPUT	442.6500	OUTPUT	442.9000	OUTPUT
442.1625	NB	442.4125	NB	442.6625	NB	442.9125	NB
442.1750	INPUT	442.4250	INPUT	442.6750	INPUT	442.9250	INPUT
442.1875	NB	442.4375	NB	442.6875	NB	442.9375	NB
442.2000	OUTPUT	442.4500	OUTPUT	442.7000	OUTPUT	442.9500	OUTPUT
442.2125	NB	442.4625	NB	442.7125	NB	442.9625	NB
442.2250	INPUT	442.4750	INPUT	442.7250	INPUT	442.9750	INPUT
442.2375	NB	442.4875	NB	442.7375	NB	442.9875	NB

Table II

Digital Voice repeater or other narrow band emission systems operating in the 23 cm band are to be coordinated on 12.5 kHz channels starting from the low end of the repeater sub-band with outputs between 1282 and 1285 MHz. Analog repeater systems are to be coordinated on 25 kHz channels starting from the high end of the repeater sub-band with outputs between 1285 and 1288 MHz. Table III below provides an example of these channels. Although this table only covers a portion of the band, this represents the typical frequency relationship utilized throughout the remainder of the band. Geographic separation similar to that presently considered will be utilized between adjacent channels. Similarly, geographic separation between co-channel narrow band systems will be considered. Adjacent coordinating bodies have not made a determination that they are prepared to announce. Digital Voice repeater systems using other formats that are not defined as narrow band will be coordinated on the frequencies typical of analog FM repeaters.

Output

Mode

Output

Mode

1282.0000

1285.0000

Analog

1282.0125

1285.0250

Analog

1282.0250

1285.0500

Analog

1282.0375

1285.1000

Analog

1282.0500

1285.1250

Analog

1285.1500

Analog

1285.1750

Analog

1285.2000

Analog

1285.2250

Analog

1284.8750

1285.2500

Analog

1284.8875

Analog

1284.9000

Analog

1284.9125

Analog

1284.9250

Analog

1284.9375

1287.9000

Analog

1284.9500

1287.9250

Analog

1284.9625

1287.9500

Analog

1284.9750

1287.9750

Analog

1284.9875

1288.0000

Table III

Digital Voice repeater systems using D-Star or other narrow band emissions and operating on the 33 cm band are proposed to be coordinated on the presently allocated repeater channels.

Organizations or individuals who presently have an analog FM format repeater and desire to change their coordination to a Digital Voice system may continue to operate on their presently coordinated repeater frequencies or they may apply for coordination to one of the narrow band (NB) channel frequencies if their system is defined as a narrow band system (occupies no more bandwidth that the typical D-Star Digital Voice system, typically defined as 6.25 kHz.).

It is recommended that these procedures continue for the near future however, it is recognized that a new 2 meter band plan must be established that may incorporate repeaters using 1 MHz splits (receiver to transmitter separation) rather than todays standard of 600 kHz splits. Development of a new band plan that would incorporate frequency splits within the FCC allocated repeater sub-band of other than 600 kHz is beyond the scope of this committee. It must be recognized that all of our neighboring coordination groups (SERA, ARCC & WPRC), the Frequency Coordination Bodies to the north and south of the T-MARC area, are all using splits of other than 600 kHz in their present coordination of narrow band repeaters in the 2 meter band.