In order to facilitate cross-band routing the APEX protocol defines several new designators as well as includes many of the old ones. Obviously WIDEN-n, GATE, and your own callsign will behave similarly to how they behaved in the old paradigm. However the new band-specific designators will have a form of ##M### or ###M## where # represents any digit 0 to 9. The first group of numbers specifies the band ID, while the second group of numbers is the net ID and is optional. In this way the designator 30M would represent the 30 meter band as a whole (specifically any nets on that band the station is capable of). When 30M is specified in a path, a station will repeat that packet out on any port which is tuned to the 30M band. Similarly 30M1 would specify a frequency (net) that resides within the 30M band. The list of identifiers for the various nets will be updated periodically as new nets show up. However right now 30M1 would specify the world wide FSK based APRS network residing on 10.1476 Mhz USB; similarly 30M2 would specify the world wide Robust Packet Radio based APRS network which resides on 10.1473 Mhz USB. similarly other designations would be chosen for other networks throughout the world. A complete list would have to be compiled.

Using these new designators in a path would be relatively straight forward. If, for example, you wanted a packet to take one hop, then move over to the 30 meter Robust Packet Radio channel, then move back to ordinary VHF for its last hop, and you do not care what the specific frequency on that hop, then you would construct your path as follows:


Notice the last hop is just 2M with no number suffix. This is because we just want it to gate into 2M network and don’t care which frequency on that band it is gating into. As a side note the GATE specifier would actually perform the same function as the 2M specifier.

Finally, when the first digit of alias is a 0 then the numbers in the first group are considered to be in centimeters rather than meters. Therefore while 30M represents the 30 meter band 033M represents the 33 centimeter band.

Generic Cross-band Aliases

The following generic cross-band aliases allow for cross band operation to specific bands, rather then an explicit frequency within them. This is useful for global operation where the local frequency used may differ from region to region.

Alias Frequency Range
023M 1240 Mhz - 1300 Mhz
033M 900 Mhz - 930 Mhz
070M 420 Mhz - 450 Mhz
1M 150 Mhz - 300 Mhz
2M 100 Mhz - 150 Mhz
6M 50 Mhz - 55 Mhz
10M 28 Mhz - 30 Mhz
12M 24 Mhz - 25 Mhz
15M 21 Mhz - 22 Mhz
17M 18 Mhz - 19 Mhz
20M 14 Mhz - 15 Mhz
30M 10 Mhz - 11 Mhz
40M 7 Mhz - 7.3 Mhz
60M 5.3 Mhz - 5.5 Mhz
80M 3.5 Mhz - 4 Mhz
160M 1.5 Mhz - 2 Mhz

Specific Frequency Cross-band Aliases

The following table gives the current frequency-specific cross-band aliases. This list is constantly growing and will be added to anytime we learn of a new local frequency utilizing APRS or APEX protocols.

Alias Frequency Modulation
2M1 144.39 Mhz (spot) FM
2M2 144.8 Mhz (spot) FM
2M3 144.525 Mhz (spot) FM
2M4 144.62 Mhz (spot) FM
2M5 144.54 Mhz (spot) FM
2M6 144.66 Mhz (spot) FM
2M7 144.93 Mhz (spot) FM
2M8 145.01 Mhz (spot) FM
2M9 145.175 Mhz (spot) FM
2M10 145.525 Mhz (spot) FM
2M11 145.575 Mhz (spot) FM
20M1 14.1033 Mhz (USB) Robust Packet Radio
20M2 14.0963 Mhz (USB) Robust Packet Radio
20M3 14.1046 Mhz (spot) FSK
20M4 14.0982 Mhz (spot) FSK
30M1 10.1473 Mhz (USB) Robust Packet Radio
30M2 10.1492 Mhz (spot) FSK
40M1 7.0473 Mhz (USB) Robust Packet Radio
40M2 7.0363 Mhz (USB) Robust Packet Radio
40M3 7.0492 Mhz (spot) FSK
40M4 7.0376 Mhz (spot) FSK
80M1 3.610 Mhz (USB) Robust Packet Radio
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