I'm flying a lot of FM these days. The band is much clearer than it was a few years ago and (I hope) it's a cheap way to get 5kms.
There is a lot of info about getting RSSI output from the futaba R149DP receiver. So I'd like to mod my rx and hopefully get RSSI output to my Trace III (or is it Trace IV?) OSD.
I've read that the RSSI voltage is between 0.7v and 2.2v depending on how close the TX is to the RX. I've not gone so far as to test this for myself.
So I have two questions for Skylark (or anyone else that's done this). First off, can you calibrate teh OSD such that these voltages are seen as 100% and 0% (does not need to be terribly accurate I guess).
Second question is, does the Trace OSD draw much current to measure the RSSI? I have heard bad things happen to the Rx when the RSSI pin is loaded down.
If it is drawing some load, then I'll make up some kind of isolation circuit to get the RSSI value into the Trace OSD.
p.s. When I get this going, I'll do a how-to for others to play with.