Hi, I think I have some kind of a problem with my servos. When I order it to move, the movement takes about 3 seconds from one extreme to the other. I use old expert S-25 servos but I think the same happens when I use new HiTec HS 125MG. 0,2 sec per 60 degrees, so 180 degrees should take 0,6 sec., am I right?

Thanks, Mark

May be a silly question, but are you sure the RX battery is fully charged? An almost dead battery will do that, and since you are saying that 2 different servos are doing the same, it has to be either the battery, or possibly the RX itself.

Yes, I was using 4 NiMH 2000 mAh AA batteries an also I tried 5V power supply. How many amps can servo take?

It could also be a switch or lead or RX problem.


David

MG: I have had simular troubles before,it always happend after a complete recharge i would do my flight chk and one servo always lagged behind so to check this i swaped servos from side to side and it still didnt change one bit,mind you this was all new equipment installed into my new aeroworks 540.well to make a long story short it turnned out to be the( generic servo extensions) i installed.so the I hope this helps

good luck Bill

unless you have a 180 degree servo you will not get 180 degree travel,most servos are set up for around 100 degree travel.retracts servos made now are 180 but not porpotional

Hi!
How old are the S-25 servos? I have old Futaba servos (S-6) from 1975 that are very slow at first (4.8V) but after some running back and forth they began to speed up. Never use them though.

Regards!
Jan K
Sweden

something like 1990

Servo's draw amps and they draw alot. If you're going to test them on a power supply make sure that the PS can deliver at least 3 amps per servo. What you describe is VERY characteristic of a servo that cannot be supplied with enough current.

The way I learnt this was that, when I was first testing my servos by connecting them to a PS I had the PS current limited to about 500mA. Because servos draw current proportional to the speed of and resistance against movement they draw alot when making big sweeps especially when connected to control surfaces.

It's also a good idea to check that your servo's don't try and push beyond the limits of your control sufaces. If they do they will be draining your battery even when they are not moving.

Does this happen when the servo is on the bench, or only when it's installed in the plane and trying to move the control surface? If it's only when moving the control surface, check the control rods for binding, this can slow the servos down.

If you are oustide, they may be cold and stiff?

Enjoy,

Jim

You can avoid questions about the quality of extensions and switch harness during troubleshooting by plugging the servos and battery pack directly into the receiver jacks. If possible, measure the voltage to a servo where it comes out of the receiver while it is in motion. This may require a second set of hands. You MUST find out what voltage the servo is getting.

Do you have your dual rate turned off so they move slow intentionally?

Dual date does not effect travel speed, only amount of travel.