User's Manual

Company Confidential 11 Raveon Technologies Corp.
4.3. Heatsinking
The M8S operates at up to 10% transmit duty cycle at ambient temperatures up to 50°C.
For duty cycles up to 50%, the module requires additional heat sinking.
If an external heat sink presses against the “GND PAD” are of the PCB, the RF power
transistor will run cooler, and allow higher duty cycles.
4.4. Mounting Holes
6 mounting holes are provided on the module. For best RF performance, the M8S module
should be mounted to the system ground, using metal stand-offs.
4.5. STAT LED Outputs
An external dual-color LED may be connected to STAT1 and STAT2 pins to show the
status of the modem. Do not connect the LED to power or ground! Connect the LED as
show below.
Because the STAT2 signal is also used to put the modem into the “bootloader’ mode, the
led must be wired as shown above to ensure a reliable start-up. The Red LED will blink
when the modem transmits, and the green LED will blink on receive of data. It will also
blink orange when decoding a POCSAG message.