Hello guys,
Lately i have been looking for a solution to convert my jets with 14 channels Futaba receivers to telemetry. these models often have 12-14 PWM channels plugged directly to the receiver.
Converting to telemetry is a problem, as the trusty Futaba R7008SB telemetry receiver is only 8 channels.
Solution #1:
To use a dual R7008SB receiver installation - one for channels 1-8 and other for 9-16. this is a viable solution, but is expensive (300$ for 2 receivers) and space / weight consuming in a small jet.
Solution #2:
Use some form of Sbus power box - again expensive and space / weight consuming for a small jet.
Solution #3:
Use a Futaba 18 channel telemetry receiver - this is a viable solution, also expensive, and it seems from the forums that this receivers suffers from a large than usual amount of failures - not an option for me.
Solution #4:
This comes from the FPV world - but proved to be quite useful for our use!
Since the R7008SB has a S-Bus port on Channel 8, which has all 16 channels data, its possible to use an expansion board such as:
https://hobbyking.com/en_us/signal-c...-pwm-s2pw.html
for 9$ and 10 grams you get 8 PWM channels (either CH1-8 or CH9-16).
This board coupled with the R7008SB would provide the following support:
- CH1-7 PWM on receiver.
- CH9-16 PWM on board.
- Telemetry support on receiver.
So total 15 PWM chanenls + telemetry from a single R7008SB receiver - not bad!
So i ordered this board and tested it - really seems to work fine. here is a test video showing a hitec deigital servo on CH9 via the expansion board:
https://www.youtube.com/watch?v=L_tt3Vy9SQk
NOTE:
one important factor to take into consideration with any dual installation is power source.
since this board conencts to the receiver using only one signal wire, while its possible to use that single line to power feed the board with its consumers, i would strongly advise against it if you are going to connect power hungry (digital) servos.
if you are using just valves, controllers or any other low current consumption devices - single wire to power the board should work fine.
if you are using more high current consumers on the board, please remove the RED wire from the wire connecting the Rx and board, and splice ("Y" connect) your power to the Rx, feeding power to the board directly. this would share the same power source between your receiver and your expansion board.
Im hoping this helps anyone that wants a similar setup.
thanks for reading.