Dave,

Good idea. I'll get a meter. As you mentioned, I initially had the servo mechanical midpoint set with the arm vertical, flap linkage adjusted for mid/takeoff, and MID on TX at zero. Then I adjusted the throw +/- for NORM and LAND as required. The buzzing at NORM/flaps-up seemed a little less with this setup.

Then, falling squarely under the "a little knowledge can be dangerous" description, I read where the flap servo spindle, arm, and linkage, should all be in a line to take the load off of the servo when the flaps are full down. That REALLY got me chasing my tail.

So, I plan to go back to the MID-zero setup. The question is where to orient the servo arm? Do I put it angled forward so that at full flap the servo arm at full-flaps is as in-line with the linkage as possible given the physical geometry of the jet? Or do I go back where at MID the arm is vertical, then angled back for NORM/flaps-up and forward for LAND/full-down?

Ross, not that misery loves company, knowing that you've had the same issue at least tells me this may have as much to do with this L-39 as anything else. In any case, I'm definitely going to get that H9 current meter so I know what's going on.

Thanks!

Randy