Servo limit testing

So, I bought a servo to play around with.

Published on Monday, 28 March 2011

So, I bought a servo to play around with, since I was over by the hobby shop the other day. The cheapest one they had was a Hitec something-or-other with "Kryptonite" gears. It's a beauty (I guess... I'm not a servo connoisseur). I tried a couple of the drivers available on and got the same results with both: the servo didn't travel anywhere near the 180 degrees it should have.

I asked about this phenomenon on the tinyclr forums, and William answered that he'd recently put together a servo tester and blogged about it. This ended being quite interesting. Using his test setup, I discovered that I had to drive the servo WAY WAY outside the recommended specs of .9ms to 2.1ms to get the full 180 degree range. I ended up at around .6ms on the low end and nearly 2.5ms on the high side.

But for a $10 servo, hey, who's complaining?