Thanks for posting that info! That might be exactly what I need to know to get the original meter working correctly. I think the old GD-19 used the meter as an RF output indicator, but converting it to battery voltage would be more practical for the conversion.Phil_G wrote: ↑19 May 2020, 11:45 Hi Dave, nice neat job, pleased to hear its working ok
Expanded scale meter example here: viewtopic.php?f=27&t=902
and theres a general meter thread here:
viewtopic.php?f=62&t=132
I used a constrain for each channel just after the 100:100 elevon mix to limit the pulses between 1000ms and 2000ms, which took care of any possibility of the ppm pulses getting out of spec.Phil_G wrote: ↑19 May 2020, 11:45 I would suggest caution with the 100:100 mixer, obviously with the stick in a corner your ppm pulses will be stretched well out of spec. Some modules and some receivers constrain out-of-spec pulse widths which causes dead areas in all the stick corners - and similarly if you constrain in the encoder after the mix, you get dead corners. The ratios are there for a reason
Relevant discussion here
While it's true that moving the elevator stick to the full up (or down) position causes both servos to reach their travel limits, and then moving the aileron stick side to side simply reduces one servo travel without any further increase in the other servo travel, this is actually my preferred elevon setup. In fact, the very first test flight of the Heathkit GD-19 conversion was with an electric elevon plane where the elevons move 45 degrees in each direction. With the 50:50 ratio mixer the elevons only reach 45 degrees of throw with the stick in the corner, and a full elevator or a full aileron stick command only moves the elevons about half the needed amount. While a 50:50 elevon mixer can work great with more gentle control throws, it wasn't practical for my particular situation of needing 45 degrees of throw in each direction for both the elevator and aileron stick commands. In fact, I also used a constrain on each of the dual aileron channels for the flapperon function so a full up (or down) elevator stick command causes the aileron servos to reach their full travel limits.
Don't get me wrong! I understand completely why you setup the elevon mixer with a 50:50 ratio. It's just that in my case, I needed the mixer to work as 100:100 instead.