PPM to Analog Converter
While ago there was a short talk in the EzUHF help thread about conversion of the EzUHF RSSI/Link Quality output into an analog voltage to feed an OSD different than the EzOSD.
I made small and simple circuit to convert the PPM signal from the EzUHF RX into an analog voltage:
The circuit uses an AVR microcontroller to read the PPM signal and an simple R2R digital-analog converter to create a proportional voltage.
An LMV358 rail-to-rail opamp is used to buffer the output voltage.
Mainly intended to convert the RSSI signal to analog, the circuit can be used for other purposes as well where you want to convert a PPM signal to analog.
The LMV358 is able to source/sink at least 50mA so a LED can be driven directly for example.
The PPM signal is considered valid between 800-2200us, where below 1000us gives 0V and above 2000us gives 5V.
Since an rail-to-rail opamp is used a full voltage swing between 0-5V can be archived.
Short video to demonstrate the funcitonality:
Hi ! i just bought a EzUHF lite 8Channels, and i was searching on how to be able to read RSSI signals with the OSD Pro from eagles Eyes. Someone on RcGroups tell me that you build this little converter. I tried to contact you via email, but can’t find, would you like to sell me one of this converter ?
it will be really apprecieted ! thanks !
For now all converter boards are sold. I plan to make some more but this will take a while, need components and PCBs first.
Did you check to produce some of these boards in shop who print pcb ? you could build 100-200 for a low cost and i’m sure they will be sold easily !
thats just an option i give to you
eheheh
That’s the way I do, but blank boards are only part of the story.
Michael, great development!
Now if only someone could get the PWM to analogue working so one could use the RSSI out from a FrSky Rx (TFR8 etc.) Some of us would be in heaven
James
Do you have any ETA when you will be able to sell more boards? Have a ezuhf system ordered and would be nice to be able to se RSSI with my ET OSD Pro
4-8 weeks
That sounds awesome, could it be possible to pre-order a unit?