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Adding Choke to controller

5163 Views 23 Replies 10 Participants Last post by  RichD
Hi all I have several controllers with variuos controlls ie brakes, sensitivity, traction control etc but would like to add a choke switch preferably on the wire cables so that I can quickly change the max voltage for a technical section of track. Ideally also with a dial to dial in the desired voltage for the switch to use (ie 9 or 10 volts).

Are there any parts that I should consider that I could get from the local electorinics shop.


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Adding "Choke" normally means adding resistance not a fixed voltage drop.
If you want a voltage drop, diodes are a good answer.
The two feel slightly different when driving a car, either is good for taming overpowered cars.

1 amp diodes (1N4002, 1N4003, 1N4004 etc.) are good for standard home set type motors and a bit above. For motors taking substantially higher current you need higher current diodes.

QUOTE (mtucker666 @ 6 Dec 2011, 08:34) <{POST_SNAPBACK}>The only diff between this and a choke is the choke will provide you max voltage at full throttle whereas the diode will reduce the voltage at all times.
That's not quite right. There are two ways a Choke or diode can be wired.
1 So it reduces power all the time.
2 So it only reduces power on part throttle but still has full power when the trigger is fully down.
Both are widely used, either can be useful. It all depends on what you want to change about the way a car goes.
Hi Kris
When using diodes to make a choke, all the motor current goes through the diode.
Diodes designed for milliamps (like most glass diodes) are not up to the job.
Rectifier diodes are designed to take amps rather than milliamps - so rectifier diodes are what you need.

For basic home set cars 1n4001, 1n4002 etc are suitable
For slightly quicker motors 1n5401, 1n5402 etc (3 amp) are better
If you are using even quicker motors the 6 amp P600 series are suitable.

You can get them from Maplin - or check our Rapid Electronics for better prices (by mail order)
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