tomfiorentino

Hey guys,

Did I read somewhere that using a digital servo to operate a retract control valve is a no no and one should use analog servos instead. Or maybe it was using a digital servo for mechanical retracts?

I'm thinking it had something to do with the way digitals resolve the signal and the way they will try so hard to center etc. that they don't deal well with the on/off positioning required for retract extremes (ie. valve on/off or mechanical wheels up/down). Therefore they draw down the battery needlessly.

Old story...bad info...losing my mind?

Not that big of a deal, but I'm about to order a mini servo for the retract valve so I'm wondering....digital or analog.

Thoughts if you have a minute would be great...

Thanks,

Tom

dasintex

My Feedback: (10)

I think your thinking about Mechanical retracts that use special Analog Retract Servos, I don't believe it matters on a retract valve; its a matter of setting your end points, centering in not an issue.

tomfiorentino

Oh good so I have my mind for another day!

I'll move forward on that basis and get the small digital and as I think about it more, you are right, centering is not the issue.

Appreciate your taking the time to chime in!

Thanks,
Tom

BarracudaHockey

My Feedback: (11)

What you dont want is to stall the servo, as long as it is setup right it won't matter. You don't want to stall an analog but a stalled digital will bring you problems quick.

BuschBarber

My Feedback: (2)

Retract servos are traditionally 180deg servos and not Proportional. I understand that there is a Spektrum Retract servo that is proportional and thus capable of setting End Points. I am told that Digital Servos are not appropriate for Flaps. I believe it has to do with the fact that the servo is never really at Neutral although Half Flap is close.

woodie

The concept of 'neutral' for a servo is a bit misleading. A servo constantly tries to match the signal from the receiver with a pot position for the servo (centering). It is never at 'neutral', it is always trying to match the receiver position signal. However, if there is a load on the servo which it is constantly trying to move to match the rx signal, then the servo will 'buzz' trying to get to that position and use more power from the receiver battery pack. The trick is to not have a constant load on a servo with draggy control linkage or a servo that is trying to move something past a mechanical limit. This holds true for analog or digital servos. The digitals will probably use more energy than the analogs but the setup requirements are the same regardless of servo type.

Woodie

tomfiorentino

Yes, yes...of course. Well put.

...like what constitues neutral for the throttle servo

Tom

rmh

any place where the servo has no load on it-is neutral

dirtybird

My Feedback: (5)

Using an expensive digital servo to operate a simple on off valve is a waste of an expensive digital servo.

pilotpete2

+1!
Pete