FPV Blog

A2 Voltage for FrSKY RX's

Voltage dividers...

Credit to Snappy FPV on Youtube for this tutorial. 

https://www.youtube.com/watch?v=21HhyyQB2RI

10kOhm, 1kOhm - for 1S - 6S Lipo
10kOhm, 2.2kOhm - for 1S-4S Lipo

 http://www.ohmslawcalculator.com/volt... for different combinations - something near smaller 3.3 Volt ist best at full lipo for a good resolution.


FrSKY Receiver D4R-II, D8R-II, X4R, X6R with analog telemetry function.
Resistor 1k Ohm or 2.2k Ohm resistor and 10k Ohm resistor


Step 1 – Prepare The telemetry Cable
Remove all wires from the telemetry cable except for the white wire
The white wire will be connected to the receivers AD2 input
Use a knife to pull up the wire locks on the connector

Step 2 – Solder Resistors
Use a Helping Hand and solder the resistors shorten and bend together
Solder a red + wire to the 10k Ohm resistor brown, black, orange end
Solder a black - wire to the 1k Ohm resistor brown, black, red end
Solder white wire in the middle between resistors

Step 3 – Shrink Tube
Use small shrink tube pieces for each wire/resistor
Use a large shrink tube for the complete wire/resistor pack

Step 4 – Measure Telemetry Voltage
ATTENTION MEASURE WITHOUT RECEIVER CONNECTED
Connect battery with your telemetry cable red + and black - wire
Connect your Voltmeter red pin with the white wire and black pin with battery -
You should measure something between 1 Volt – 2 Volt, if you measure your battery voltage then your wire/resistor connection is reversed

Step 5 – Setup your Receiver RX
Connect your white wire connector with your receiver
Connect your receiver with your Flight Control or ESC 5 Volt source
Connect battery with your telemetry cable red + and black - wire

Step 6 – Setup your Transceiver TX
In Telemetry Menu setup A1 Voltage Divider Receiver 5 Volt – Range 13.2v
Setup A2 Voltage Divider 3S/4S Battery – Range 36.6v
Voltage for A2 Channel should now nearly the same like your battery voltage
Setup your Warnings for example 10.7v and 10.1v