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Discussion Starter #1
I recently obtained a Harvester from a local yard sale. Cosmetically, he is in great condition. No dirt anywhere on his inside or his clothes. The problem I am having is with his head rising mechanism. His eyes, mouth, and head turn all work great, however his head doesn't lift up or down. You might think it could be a split gear, but both wires are on the motor and the mechanism moves freely without any crackling or too much resistance. The motor doesn't buzz at all. I checked the wire harness and all the pins were fine. I even opened the box up to his circuit board, and his circuit board is clean and good. The wire harnesses there checked out as well. Even the relay switch to stop the neck mechanism works, because if it is pressed the head doesn't self-reset when switched on for the first time. I doubt the motor is the problem because it looks so clean, however maybe it is the problem and it is just worn out? What do you guys think?
 

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Discussion Starter #3
You are right about that. I do have a few spare motors lying around doing nothing, so I'm gong to try replacing it. I'll update this thread when I finish.
 

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Discussion Starter #5
I do have an older mechanical multimeter, but I don't really know how to use it. How would you check for current?
 

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I do have an older mechanical multimeter, but I don't really know how to use it. How would you check for current?
Set the meter for DC volts. With the meter leads on the motor connections, activate the prop and see if there's voltage actually going to the motor when the head should raise. If not, the problem is something other than the motor.
 

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Discussion Starter #9
Well my damned multimeter isn't functional, so I just went ahead and switched motors with 2 separate ones that I knew worked. No luck at all. It is an electrical problem, and I hope to find a solution.
 

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I would invest in a cheap multimeter. Harbor Frieght gives them away for free sometimes. I still would check for working voltage at all motors. Did you use the exact motor when switching it out? If you use a higher voltage motor and the power is lower(eg 12v motor with 6v power) there is a possiblity it will not move. I would check for continuity in the wires, you may have a break that you can not see. Set you meter to continuity and test from the jack to the board. If you hear a beep then there is no break. If you here nothing then you have to rewire it and crimp new molex pins for the plug.
 

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Discussion Starter #12
Good news: I have obtained a working multimeter once again. I will promptly try to test for any current, and for a break in the circuit like you guys recommend. I will keep this thread updated.
 

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The motors I tested were exactly the spec of the old one, by the way. Not even a flinch.
Well, if you know the motors you tried were good, no use in checking for current. Unless there's a broken wire from the circuit board to the motor, the problem is most likely somewhere on the board.
 

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Discussion Starter #15
According to the multimeter, the wires all check out and work. The current from the board to the motor should work, yet it doesn't. I've attached some pictures of the circuit board here, and the 2 pins that go to that motor are directly under C15. Can you guys identify anything wrong with the board?
 

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Without any noticeable burned areas, it's almost impossible to even speculate where the problem is. One thing that did catch my attention though is that yellow jumper wire soldered to the board. That seems odd, especially since this was from a garage sale. Honestly, you're luckier than with most used props of this nature, everything works except the head up/down.
 

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Discussion Starter #17
Well, unfortunately, I believe the head tilt will never work. Due to the newness of the board and the micro- components, it is near impossible to try to replace anything, let alone trace the electrical rail. I ever reheated the solder joints, to see if any of them were just cold, but this yielded no success. The prop is still cool, but it is sad that the head tilt (one of the selling features of the prop for me) doesn't and will not work. This even could have been a factory error, because the new boards are more precise, and we all know that those Chinese companies aren't very familiar with that in their manufacturing process. If the whole thing eventually does die, there are plenty on eBay right now for good prices. Thank you all for helping!
 

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What's the sequence of operation when the prop is triggered? Does the head raise motor need reverse voltage to lower or does it just fall when the motor power is cut? If I know how it operates I can program a small controller to just handle the head raise portion.
 

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Discussion Starter #19
I know that the motor requires voltage to bring the head back down, and there is one singular relay switch that stops it when the head is pulled up. Still, it is very nice of you to throw together some programming for it, if that is something you would like to do. If this something that I decide to incorporate into the harvester, would I require any additional hardware? I have a raspberry pi lying around. Even still, I would want this prop to be displayed outside, and not next to a computer. I may just look at getting another one at this point.
 

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No PC would be needed, just a small controller to operate the head up/down. I would need to know exactly how the head motor functions and any limit switches and/or relays connected to the motor.
 
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