The Tracker2 series has been discontinued.
Tracker2 OT2m manual (English)
Tracker2 OT2m manual (Simplified Chinese)
Fleet Management Interface
The Tracker2 supports the Garmin FMI protocol for position data, text messaging, and tracker control. See Garmin's list of FMI-capable models.
The Tracker2 has been produced in a number of variations.
OT2m Stand-alone unit in a metal enclosure
T2-135 Plug-in board for the Alinco DR-135
T2-301 Plug-in board integrated with the FC-301/D transceiver
Archived documentation for Proto A, B and C models is available here (zip archive).
Proto E - Identical to OT2m v1.0 with the exception of some PCB markings, thermal vias, and C2 being replaced by 0.001uF cap.
Proto D - Flawed prototype, never released
Proto C - The most widely distributed version during beta testing. Proto C and earlier used all through-hole parts and had a passive input filter.
Proto B - Early prototype with limited production.
Proto A - Early prototype with limited production