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Need help identifying this

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spec

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Hi MG,

It looks like a wire-wound power resistor.

spec
 

MikeMl

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NiChrome-wire-wound power resistor, likely low-Ω, rated for ~5 to 10W. Do you have an Ommeter? If so, measure its resistance.
 

MikeMl

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MikeMl

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Found it at Rat Shack, of all places... You didn't put in a country when you registered for this forum, so don't know if any of the these vendors are appropriate...
 

audioguru

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The leads on my multimeter measure about 0.3 ohms so maybe you are measuring the resistor of only 2.2 ohms plus the 0.5 ohms resistance of your meter's leads.
Since it measures correctly and looks OK then why do you think it needs replacement?
 

audioguru

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Is the resistor in the car or is it part of the rheostat in the remote control that controls the car's speed?
 

M Godwin

New Member
The leads on my multimeter measure about 0.3 ohms so maybe you are measuring the resistor of only 2.2 ohms plus the 0.5 ohms resistance of your meter's leads.
Since it measures correctly and looks OK then why do you think it needs replacement?
I agree and the motor works so there must be a another reason why the wheels are not turning, problem might be in the remote. Wiring in the remote are connected but must be some other problem.

I really appreciate all the help
 

KeepItSimpleStupid

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M: Something that works a lot of times is to remove the batteries and short the battery terminals to the device. The shortest time I used was about 30 seconds and the longest overnight. With a device I did not have easy access too (A home thermostat), I removed power for 2 weeks and installed a TVS diode. So far, 2 years and no backlight turn-ons.
 

Nigel Goodwin

Super Moderator
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At a guess, and considering the age of the car, it could be part of the (crude) steering servo arrangement - with a sliding contact moving along the wirewound resistor a simple non-electronic servo mechanism. In the old days such crude systems were common, as complex IC's for servo systems didn't exist yet.
 

spec

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Those resistors are notorious for the contacts going open circuit/high resistance where the terminal/wires connect.

It is best to do an end-to-end check:
Get two needles and connect one to each test lead of your meter.
Push the points of the two needles through the insulation of the wire connecting to the resistor and make sure the reading is around 2.2 Ohms.

spec
 

Tony Stewart

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If you can measure, the resistance, what is the fault?

If I were designing a powerful motor with no space for locked rotor heat, , I would add a PTC nichrome resistor like this not a fixed R.
 

RODALCO

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You can find that type of wirewound resistors on old pre 1975 car voltage regulators which had a generator instead of an alternator.
 

Les Jones

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Hi MG,
Can you clarify what you mean by turning the wheels. Do you mean turning the wheels to drive the car (Propulsion.) or to change the direction of the car (Steering.) ? If it is steering can you trace the wiring for the steering motor servo system ? There will be a potentiometer that provides feedback of the steering direction. There will also probably be two relays or a number of power transistors which will probably be germanium rather than silicon from the age of the toy. Some close up pictures of the steering mechanism would also be helpful.

Les.
 
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