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Power – J3 (also J1 and J2)
TinyTrak3 must be powered with an external source of 7-35 volts DC, such as a 9-volt battery, or a 12-volt cigarette lighter
plug. TinyTrak3 is NOT powered via a computer’s serial port. Power can be applied via J1, J2, or J3. J1 is the most
common way to power the TinyTrak3. To use J1, connect pin 7 to positive voltage and pin 6 to ground. To use J2,
connect pin 4 to positive voltage and pin 5 to ground. Also, short J7 on the back of the PCB by dropping a bead of solder
across the two square pads. To use J3, apply positive voltage to the plus (+) hole, nearest the LEDs, and ground to the
minus (-) hole. Only one of the three jacks J1, J2, and J3 should be used to supply power to the TinyTrak3. If power is
applied via J2 or J3, the same power will be available on J1 to power a radio. If power is supplied via J1 or J3, the same
power can be retrieved via J2 to power a GPS, if J7 is shorted. Be sure not to draw more current than your supply can
handle. At 12 volts, current draw is 6.6ma + 3ma for each LED lit. If desired, the 4 1K LED resistors can be replaced with
10K resistors, which will cause the LED to only draw about 0.5 ma each.
LED Control – J4
This optional jumper is normally bridged on the PCB, but if desired, can be cut, and replaced with a true jumper. This will
allow easy disconnection of the LEDs if current saving is important. If desired, cut the trace between the two J4 holes, and
insert a 1x2 header.
Primary/Secondary Switch SW 1 – J5
This switch input will select the primary or secondary operating parameters. When left floating, or at 5 volts, the primary
parameters are used. When grounded, secondary parameters are used. Whenever this switch is changed, the timers
are reset, the Carried Detect LED (D2) will blink rapidly for a short time, and then a transmission will be sent. SW1 is also
available on J1 pin 4. This switch input is optional, and can be left unconnected.
Power Switch – J6
J6 can be used to control power to the radio and/or GPS. TinyTrak3 can be configured to assert J6 with 5V just before a
transmission is sent. After the transmission, J6 will drop back to 0 volts until the next transmission is ready. Be sure to
choose a relay that can handle the power requirements of the radio and GPS. A Radio Shack 5VDC Reed Relay (275-
232) can be used to control power to a radio that draws less than 1 amp. J6 can only supply 25ma. This output is
optional, and can be left unconnected. See the Power Switch section in the Configuration Software.
Serial Power Enable – J7
To bridge serial power J2 pin 4 to TinyTrak3 power J3 and J1 pin 7, this jumper on the bottom of the PCB should be
shorted by dropping a bead of solder across the two square pads. This will allow the GPS to receive power from the
TinyTrak3 power source, or let the TinyTrak3 be powered from the serial connector. If serial power is not needed, leave
this jumper open.
Operations
Configuration Software
To set user options, such as call
signs and transmit rates, use the
TinyTrak3Config.EXE program,
available from www.byonics.com.
First, power TinyTrak3 via an
external battery or other power
source and connect it to a
computer serial port. The computer
serial port wil NOT power the
TinyTrak3. Be sure to use a
gender-changer, and a null-modem
adapter. Launch
TinyTrak3Config.EXE, and select
the connected serial port. Click
“Version” to confirm the config
program can communicate with
TinyTrak3. If a firmware version
number is reported, the software
and circuit are communicating. If
