HiTEC HS-7985MG Digital Coreless Servo Jitter
05-17-2010, 04:48 PM
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HiTEC HS-7985MG Digital Coreless Servo Jitter
HiTEC HS-7985MG Digital Servos Jitter:
Brand new servos, on elevators of 35% Extra 260, jitter under only the elevator weight, and will not stop no matter what I do. Adjusting to a higher dead band makes no difference. All linkage is firm and not binding. Lifting the elevator weight off of the servo linkage stops the jitter. What is the problem? I have never had servos to persistently jitter like this. Anyone with a solution?
RalphB
Read more: http://www.rcuniverse.com/forum/m_96...#ixzz0oDwFzLd2
Brand new servos, on elevators of 35% Extra 260, jitter under only the elevator weight, and will not stop no matter what I do. Adjusting to a higher dead band makes no difference. All linkage is firm and not binding. Lifting the elevator weight off of the servo linkage stops the jitter. What is the problem? I have never had servos to persistently jitter like this. Anyone with a solution?
RalphB
Read more: http://www.rcuniverse.com/forum/m_96...#ixzz0oDwFzLd2
05-17-2010, 04:56 PM
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RE: HiTEC HS-7985MG Digital Coreless Servo Jitter
If you are using a JR Power Safe receiver, you need signal boosters if your servo leads exceed 20".
These can be purchased for Horizon Hobby. Or, Emcotec in Germany.
These can be purchased for Horizon Hobby. Or, Emcotec in Germany.
05-17-2010, 05:49 PM
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RE: HiTEC HS-7985MG Digital Coreless Servo Jitter
My on-board system is as follows:
Fromeco 2600mAh, 7.4 volt Li-ion dual battery packs on MPI Miracle Switch 6V. voltage regulators, both to the one receiver, a Spektrum DX7. There are long leads exceeding 24" to the tail servos. The rudder servo is a very high torque HiTEC digital servo, which is steady, never jittering - of course there is no rudder surface load on it at rest. So these long leads to the tail need signal boosters in the lead at the servos?
Fromeco 2600mAh, 7.4 volt Li-ion dual battery packs on MPI Miracle Switch 6V. voltage regulators, both to the one receiver, a Spektrum DX7. There are long leads exceeding 24" to the tail servos. The rudder servo is a very high torque HiTEC digital servo, which is steady, never jittering - of course there is no rudder surface load on it at rest. So these long leads to the tail need signal boosters in the lead at the servos?
05-17-2010, 06:18 PM
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RE: HiTEC HS-7985MG Digital Coreless Servo Jitter
Only if you are using a JR Powersafe receiver, JR922 or JR1222. You are not using one, so should be working Ok.
05-17-2010, 07:22 PM
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RE: HiTEC HS-7985MG Digital Coreless Servo Jitter
Give the Hitec guys a call, they will be able to assist. Perhaps the DX7 receiver provides signal voltage in the same way as the 9 and 12 channel powersafe receivers. If this is the case, the signal boosters would be a good test. Call Hitec, they will know for sure. How long are the leads on the servo with the jitters?
05-20-2010, 05:24 PM
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RE: HiTEC HS-7985MG Digital Coreless Servo Jitter
I have the following reply, explanation from Hitec -
"All Hitec digital servos will exhibit some jitter with a slight load on them, like the weight of a control surface. Once flight loads, or zero loads are realized it’s not there. So, yes it is normal and you should not worry about it because it will not affect your model in flight.
Mike."
"All Hitec digital servos will exhibit some jitter with a slight load on them, like the weight of a control surface. Once flight loads, or zero loads are realized it’s not there. So, yes it is normal and you should not worry about it because it will not affect your model in flight.
Mike."
