RCSoar

I have a Hitec 5125 wing servo which is stalling at about 3/4 travel of stick travel, it looks like it's hitting an internal mechanical stop.

My question is - (a) is this a common (QC?) problem on the 5125 and (b) has anyone managed to fix it by adjusting the internal pot mechanics? It's easy to do on Volz and other servos but I don't want to open up the 5125 (which involves removing the labels), and find that the pot is inaccessible or cannot be adjusted relative to the shaft.

The servo is new, because time is short I'm prepared to fix it myself rather than returning it.

Thanks in advance
- Mike

mglavin

My Feedback: (31)

Can we assume you have turned up the ATV or end-point adjustments? A Dual-Rate is not activated?

Have you tried the servo on another channel to verify the servo is the problem?

RCSoar

Yes, forgot to mention - the servo was tested using a 'test' channel with the default travel (100%) and centring (0%), no trim input and no mixing. My other 5125's servos work fine. I can measure the pulse width and the servo is hitting the stops at around 1.8mS pulse. Nominal range is 1 - 2 mS.

mglavin

My Feedback: (31)

What about the programming of the servo. This is a Hitec Digital servo, therefore its programmable. Do you have access to a programmer? If so reset it and set the end-points to your needs. If not sounds like you'll have to return it to Hitec with a note or possibly your Hobby Shop can exchange it for you..

RCSoar

Futher thoughts... the servo centre is occasionally jumping 5 degrees or so either way, and pressing down on the servo arm can cause malfunction. This would help confirm my suspicion that the pot is slipping on the shaft.

I was hoping that somebody might have opened upa 5125 to see easy it is to reposition and secure the pot to the shaft.

- Mike