Jeff's RC Site - Electronics & Wiring

Most of the information on this page can be applied to
Mechanical Speed Controls and Electronic Speed Controls
MSC and ESC respectively
ESC's can be costly and temperamental not to mention if one gets wet, most likely it's going in the trash.
See Speed Controls for more info on ESC's
MSC's are more durable, cost effective and work even when wet, but do have baggage such as a independent power source, no warning if power is getting low and require more space.

Wiring Tips
Never just twist the wires together, always use solder and heat shrink tubing.
A soldering iron can cost as little as $5 and the heat shrink tubing keeps moisture from the wires and looks more professional.

Clean the tip of the soldering iron with sand paper before each use and
an adjustable holder that has alligator clips to hold the wires.
Heat the wire first, then add the solder and hold until it looks like it absorbs it, the same on motor and micro switch tabs.
Even though solder has flux added, I keep a bottle handy for the stubborn jobs, you know the ones where the solder stays as a ball or rolls off

All illustrations were created by me
If you would like to use them on another site
Please ask

In-line motors are wired in series;
Battery red power (positive) connects to the positive of the first motor, the negative of that motor (green) connects to the positive of the second motor, the black power (negative) connects to the negative of the second motor. When 14 Volts are sent, the two motors split the voltage, each running on 7.2v

You can use the same battery connector harness to supply 14 Volts to the Graupner 700 motor.
See below.

ESC's do not work well with this configuration

Wiring concept for a single or side-by-side motor(s) with two batteries

An ESC can be used in this configuration

Parallel is used to convert a single battery connection to a dual
Dual battery advantages are balance and longer run time.

Purchased parallel Y-Harness

Series is used to add the voltages of two batteries
I have never come across a manufactured version of the this harness
I have made them from the parallel harness

Servo is mounted so that the control arm can actuate switch levers. Power is cut when switch 1 (SW1) is actuated Power is in parallel when no switch is actuated, 7.2v Power is in series when switch 2 (SW2) is actuated 14.4v Switch 2 is two lever switches one on top of the other, the levers are connected together so they can be actuated at the same time. O = Circuit is open when lever is Not depressed C = Circuit opens when lever is depressed	SW1 is at top of picture SW2 is at bottom of picture
	There are two manufactured versions, by Graupner & MRP I have used both and have had to replace them due to switch failure and the mounting method to the servo.

Simple on/off power
Base mounted switch
	Do Not mount a switch to a servo Done it and fried the servo. When contact is made it sends a pulse that will knock out the electronics in the servo.

Micro Switch, also known as: Lever switch & On/Off switch
This is a 16amp sold by Kyosho $13, you cannot just find these anywhere, most electronic stores like Radio Shack only sell as high as 3 amp switches which will run the motor for a millisecond before it melts.
Golf Cart part stores sell these at a fraction of the cost.

Non ESC or BEC setup.
If your receiver has BEC (Battery Eliminator Circuitry) you can use an ESC (Electronic Speed Control) which will provide power.
Custom Battery for Receiver This is a 5400 mAh battery pack I made from a laptop battery pack which had 8 of these cells at 4.2 volts each. I soldered a male connector so that it can be charged (at trickle) with my RC chargers, then I soldered the female connector to the switch that powers on the receiver. With the two cells in parallel, it can last 20 or more runs.
Radio four Cell Battery Case If you use one of these you should get rid of the connectors and solder the wires direct, the connectors corrode easy. Wrap a rubber band around it so the batteries are not jarred loose. Remove batteries & dry after use, same as the connectors, the battery contacts corrode and break free. If any of the above fails while your boat is running, it will run at high speed with NO control.
Radio Servo Switch Harness Remove connectors and wire direct with solder and heat shrink tube.
Futaba style Radio connector If you have Futaba style connectors with the tab on the side, it can be trimmed off to fit other brand receivers.
Futaba Radio receiver B is for the power connector 1 & 2 is for servo and/or ESC connection. The wire is the antenna which should be fed through a plastic tube mounted on the boat and extended to it's full length. Never cut the radio wire.