servo issue

[Nicolasmj]

I just bought a hitec 82mg mini servo to shift my transmission on my wraith.
I plugged it into the RX with no horn and powered up. I wanted to set end points and such before hooking up linkage. The RX and this servo are powered by my MMP. All other servos are on the cc bec. Once powered up it buzzed like crazy and when moved it would be sluggish and sloppy looking and getting hot quick. If I cycled is slowly from end to end and back to end it would be quiet but if I hit the shifter to its preset it started buzzing again. I would have to cycle again to stop it(slowly). It finally stopped randomly and I hooked up linkage. Now every time I turn it on it buzzes until I pull from the end point 1-2 points on my 4pl. When I shift I have to shift then pull back. Then re add when I need to switch back.

Thoughts?

[Johnnysplits]

You should try hooking up the linkage first, set the epa to like 30 then adjust up from there.

[Nicolasmj]

Already set now but it buzzes and I don't want to kill it if I have a gremlin. My last bigger servo does the same thing with no linkage. After three minutes of testing it will be hotter than you want to touch. That one is the stock wraith steering servo. It got so bad that is would draw enough to hicup the RX with the linkage on. I tried a 7954sh and it was fine but a little overkill.

[Johnnysplits]

The only thing I can think of is that the epa is set too high. Wish I could be more of a help.

[Norton]

Are you using a 3 position switch? I use a 4PL for my dig unit on my Crest for all three positions. On my SCX10 I use the same switch for a RC4WD 2 speed. But I did have to program it differently.

[Nicolasmj]

Yes I'm using a 4pl and the three position switch. The problem is if I get it to the point where it doesn't buzz when I shift to one gear then back it won't engage enough to get in gear. Maybe I'm overthinking the buzz and let it stay for a few runs. Going to try adding a spring linkage to help save the servo.

[Charlie-III]

Digital servos tend to buzz, moving the servo arm a little bit usually quiets them down. This appears to be an analog servo, though they can still buzz some.
Powered down, does the servo arm move freely? I have seen some arms (cheap aluminum clamping) actually contact the face of the servo adding a TON of drag. That's how I killed a HiTec 7950.

[Nicolasmj]

I'll check but it is a plastic arm that came with.