Hi All
I'm trying to locate a suitable simulator signal in my Venom 35MHz 4 channel TX and although it has what appears to be a trainer port I can't find an appropriate output on any of the 4-way mini-din pins. I've unfortunately only got a PC based Oscilloscope and as it uses the mic input (AC coupled) can't see DC levels.
I've tapped off one side of the xtal (see link: http://sdrv.ms/15AZh9B) and using SmartPropoplus+Vjoy have FMS operating well, but the 650mV (I think) signal level is not suitable for the Phoenix USB input box - it can't see the transmitter. It could have a significant DC component, in fact it does as my DVM indicates on average 2.5V.
Questions:
what signal level is required by the USB device; I suspect CMOS (5v) or it could be TTL (0-2.4V), perhaps the input is already AC coupled in the USB interface?
what signal level is traditionally output from training ports/Simulator outputs of training port?
Options: assuming TTL/CMOS requirements for USB interface, I could use a DC restoration circuit (diode, resistor, small cap & op-amp (gain 10ish) or simply find a compatible PPM output on the IC - maybe that's easier!?
Your advice would be greatly appreciated.
Lea