frequent flyer

My Feedback: (6)

I wonder what is happening. I had some older servos with plugs that did not fit my current Futaba "J plugs", so I bought some leads with the futaba "J connectors " and solder them onto the old servos.
When I hooked them up they shake, gidder, back and forth?
Some said "IC" on them. What does that mean? Does that have anything to do with it? Some were cirrus servos and some were aero sport servos if that helps.
Do any of you know why ? Can it be corrected? Are these just not compatible?

bob_nj

My Feedback: (62)

Do all of them do the exact same thing? What is the voltage on your battery pack? Can you test a known good servo on the battery and receiver? Are the Tx and Rx modulations the same, FM-PCM? Check some of these items and let me know. Good Luck_bob

frequent flyer

My Feedback: (6)

Yes, the radio and receiver are brand new fm Futaba. I hooked up everything , fully charged all overnight. The battery is the standard 4.8 volt. The new radio system and all new servos work perfectly.

All that I did was put a new lead/plug on an old aero sport servo, plug it into the receiver and try it. It goes back and forth fine but when in the netrul position it gidders. None of the other new servos do. It seemed odd to me that it would not work. I thought that all servos worked with any radio system. I have a bunch of these servos from old am and fm radios that I no longer use. I thought that I could just put a new lead wire with the futaba j plug on them and use them at least for a throttle, choke, or on the kill switch of some of my large scale planes that I am curently building.

strato911

Sounds like the feedback potentiometer is worn out near the center. It can be replaced.

Not all old servos can be used with new equipment, but most of them can. Some older systems used a different signal pulse length to represent center. Modern radios use 1.5ms center, but SOME older radios (more than 15 years old) used 1.3ms or 1.6ms pulses for center.

frequent flyer

My Feedback: (6)

Oh really, well all of these servos are more than twenty years old. Does that mean they are junk box material?

strato911

I would "jury rig" a temporary connector and try it. Watch for binding when you move the sticks to their extremes. Don't forget to set your end-point adjustments to maximum on the Tx. Like I said, most older servos can still be used.

bob_nj

My Feedback: (62)

They may or may not be "junk" as you put it. Being so old though, there is a chance that they are used to the point of the pots wearing as stated above. Things were different back then technology wise. I used to change all of my own pots and wipers. Wouldn't think of it now_bob