user manual

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- JR DMSS
The SparkSwitch PRO must be set to the JR telemetry system.
Connect the RX input on the SparkSwitch to the receiver’s switch channel, then
connect the Telemetry output on the SparkSwitch to the receiver’s SENS input
using the second patch lead.
The telemetry data are displayed on the transmitter as F-PACK (V, C, A), Temp. and
RPM.
3.7. INSTALLING THE TEMPERATURE SENSOR
The temperature sensor is attached to the cylinder
head using a ring-screw. This requires a 3.5 mm Ø
hole to be drilled in one of the engines cooling ns.
You can then screw the temperature sensor in place
using a suitable self-tapping screw or M4 machine
screw. A small quantity of heat-conducting paste un-
der the sensor will improve the temperature measu-
rement. Ideally the attachment point should not be in
the propeller’s airow, as the ow of air would tend to
falsify the cylinder head temperature.
3.8. RPM MEASUREMENT
The Signal pin at the output of the SparkSwitch, which runs to the ignition unit’s
power supply, can be used for measuring engine RPM. Most ignition units (3W,
DLE, DLA) have a “Tacho” output whose signal can be run directly to this pin. The
SparkSwitch can measure the rotational speed pulses if the ignition unit’s power