Model Boat Mayhem
Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: funtimefrankie on February 18, 2011, 09:11:21 am
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I'm trying a bit of plastic magic with a toy boat , I've used a micro servo, cirrus rec , a micro mtroniks ESC and Marks Model bits mini motor.
I've fitted the three suppressors that came with it but the whole lot goes mad when switched on, the motor stutters one way and barely runs the other the servo shoots to hard over.
As it's all very small there's no scope for moving the components apart.
Any Ideas???
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Got any photos ?
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Is the power supply stable?
What happens when the servo/ESC are transposed?
Unstable power will cause jitter, locally generated interference can put a false signal to the steering servo (channel 1?) depending on the radio type.
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You are not trying this out near fluorescent or strip lighting are you.
I have a work lamp that that drives my RC stuff mad when switched on.
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Have you tried turning on the transmitter first?
Before you turn on receiver and the bits in the boat.
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Photos to follow, been fitting a new fence panel this morning :((
Not near a fluorescent light, xmitter on first, power supply Ok.
I think I used different channels, but I'll try that again, when I do the pictures.
Frank
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I'm using a well charged 6v LA, changed everything, but the motor, with the same results.....
In pic 2 only the servo is fixed, the rec and ESC are just sitting there, when trying I lift them out of the hull.
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If the symptoms follow the shuffling of the items plugged into the RX, my next move would be to temporarily swap parts with ones known to work. Most faulting assumes one single cause, but this is not always the case. Use a known working servo as a "meter", just on its own, then try a different RX borrowed from a known working model.
I have a servo tester for times like this, and, at the cost of two really cheap servos, I wouldn't be without it.
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Everything except the motor has now been changed, (same xmitter and rec crystal)
ie different rec, different ESC, different servo,.....
so I'll have to have a search round in the shed for a different motor.
It's Ok with the orginal set up but the motor wires dissed
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There are broadly two ways you can get interference - via radio waves, or as pulses reflected back down the motor wires.
The capacitors suppress the sparks, which radiate in the RF ranges. But you may have a lot of pulsing coming back down the motor wire. The way to suppress that is to use a ferrite ring or bead, and wrap the motor wires round that a few times. Here is a little illustration: http://hobbywireless.com/cart/index.php?main_page=product_info&products_id=91
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A good drawing on that link, the important bit is that the wrapped wire should be tight on the toroid, and kept that way, and there should be no overlap between the one end and the other, else the interfering signal gains a by-pass path. Can be annoying, that.
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I've now put a motor in recovered from a disc drive ( I think), same size shaft :-)) and it runs a treat.No glitches,and not suppressed, unless they are inside somewhere,
Even had a trip round the garden pond,
I'm using 4 AAA bats I think it could take a bit more weight so I might try two more for a bit more speed.