Homepage:
Manual: http://www.tigertronics.com/files/tm1man.pdf
The Tigertronics TM-1+ is located inside the flight capsule. It receives an information packet from the microprocessor every fifteen seconds using an RS232 serial connection. One modification was made to the modem such that the modem turns on when power is applied. The modem converts the information it receives into an AFSK audio signal that is sent out at 1200 baud.
An example transmission is broken into its component parts below.
Ouptut:
KE7GDZ-3>KE7GDZ:RISE,528,15:01:10,A,4719.2423,
11724.2964,8.4,264.5,1775.0,1.0,10,817,1010,1267,1865,2.809
KE7GDZ-3: Originating call-sign
KE7GDZ: Receiving call-sign
RISE: Our identifier
528: packet number
15:01:10: Time of transmission (referenced to GMT)
A: indication that GPS data is valid (V is invalid - don't ask why)
4719.2423: latitude (47 degrees, 19.2423 minutes)
11724.2964: longitude (117 degrees, 24.2964 minutes)
8.4: Ground speed in mph
264.5: Course heading (direction of travel)
1775.0: Altitude in meters
1.0: Horizontal dilution of precision - a measure of how accurate the fix is
10: Number of satellites the GPS is receiving
817: X axis acceleration (to convert to g's, use formula f = 5*x/2048 - 2.5, where x is the reading).
1010: Y axis acceleration (use same formula to convert to g's)
1267: Z axis acceleration (again, use same formula)
1865: Battery voltage (use formula V = 20*x/2048, where x is the reading)
2.809: Core voltage (the voltage the microprocessor uses for it's operation - should always be about 2.8)
