Table of Contents
RC Hobby Electronic Speed Controls
The TCB has eight RC outputs, and numbers 1-4 are dedicated to:
1. Left tread (or drive channel for cars)
2. Right tread (or steering channel for cars/halftracks)
3. Turret rotation
4. Barrel elevation
Of course you are free to use other sources for those functions, for example you may choose to drive the turret motors with the onboard controllers and the drive motors with a serial controller. Any of these four RC outputs not used for primary functions listed above will become free to use as a general purpose outputs (see the RC Passthrough functions in the Function List).
An RC output works the same way that an output on a standard hobby receiver does. You can plug a hobby ESC (electronic speed control) or a servo into any of them. On this page we are going to discuss ESCs (see here for Servos). The TCB is compatible with both brushed and brushless ESCs.
Warning! Almost every hobby ESC today includes a BEC (battery eliminator circuit) - this includes the Tamiya DMD! The purpose is for the ESC to provide 5v power to the radio receiver and subsequently the servos in a typical hobby application (which “eliminates” the need for a separate receiver battery). However, because the TCB already has its own 5v supply, you must disable the speed control's BEC before plugging it into the TCB, or you could damage one or both!
Disabling the BEC is very simple, you only have to remove the center pin of the speed control plug (typically red or orange in color). The pin can be replaced later if you decide to use the speed control for some other project, so it is not destructive in any way. Here's how:
Connecting to the TCB
Most RC car ESCs implement a brake mode that prevents the speed control from changing direction immediately. This is fine for RC race-cars but will not work with tanks. If you have this type of ESC, you need to disable the brake or put it into “crawler” mode. Some very inexpensive Chinese speed controls will only have a single mode, so do not buy one that has a brake if it can not be disabled.
Almost all RC tanks today use brushed motors, whereas much of the RC car scene has moved to brushless. There are countless brushless car ESCs available, but finding a good brushed speed controller can sometimes be difficult. But don't worry, we did the research for you! (Of course you can still use brushless if you prefer.)
HobbyKing XCar 45A
To date the absolute best choice for 1/16th scale tanks is the Hobby King X-Car 45A ESC. Yes, that's 45 amps! (Which is way more than you'll ever need). The best news is, these speed controls only cost about $10 US each!! Of course you will need two for your tank, but that is still 1/3 the price of a Sabertooth 2×5 serial motor controller. Unlike the Sabertooth the XCar ESC does not operate at ultrasonic frequencies so you will hear a small amount of motor whine. However they are infinitely better than stock Heng Long or Taigen (or even Tamiya!) MFUs, all of which operate at around 1-4 kHz, whereas the XCar operates at approximately 8 kHz (20 kHz is considered beyond human hearing).
Note: The XCar 45 ESC is limited to 2S Lipo input, or 5-6 NiMH/NiCad. In other words - don't run it with a 3S Lipo.
The XCar 45 has two modes that can be selected with the pushbutton on the unit. The manual calls these “Practice” and “Climbing” but in RC car terms they are better called “Blinky” and “Crawler” mode. For use in tanks, you want to set them to Crawler mode:
- Connect a motor to your ESC
- Apply power to the ESC
- Press and hold the button on the ESC for two seconds until you hear 2 beeps and the LED turns solid.
- That's it.
- If you press and hold the button and you only hear 1 beep and the LED starts blinking, simply press and hold the button again until you hear 2 beeps and the LED turns solid.
- Now that's really it.
- The ESC will remember your setting so you only need to do this once.
Banggood 10A Brushed w/o Brake
Banggood sells a very small and very inexpensive 10A brushed ESC. It is rated for 2S Lipo or 7-cell NiCd/NiMH with 2KHz operating frequency. Be sure to get the version without brake. You can buy two of these for less than $15 US shipped. Even though it is very small we believe the 10A rating to be a reasonable claim as the MOSFETs on the board (UBIQ QM3006M3) are actually rated for much more, but given the lack of heatsink and thermal constraints 10 amps is probably just about practical.
You will want to replace the motor/battery connectors and we would simplify the wiring by eliminating the on/off switch.
Remember to remove the center pin from the servo connector!
AliExpress 20A Dual Brushed ESC
AliExpress has an interesting dual 20 amp speed controller in a single physical package for a very reasonable price. Remember to remove the center pin from the servo connector!
Status: Tested by forum user and reported to work very well!
The DMD is included with Tamiya's RC tank kits and is basically a box with multiple brushed ESCs built in. There have been several versions over the years including the T-01, T-03 and T-08. Most include 4 brushed ESCs with an integrated “V-Tail” mixer for the tracked drive and two additional 3A outputs for elevation and rotation motors. It is controlled with standard RC signals like any other hobby speed controller. Because of its incredible expense there are many better options than buying one outright, but if you already have a DMD from a Tamiya kit you can use it with the TCB.
Because the DMD performs the mixing function for both tracks the TCB needs to know not to add its own mixing. On the Motors tab of OP Config you want to select Tank (Tamiya DMD) for the Vehicle Type. The Drive Motor will then automatically be set to RC Output and the TCB's internal mixing turned off. Connect the DMD Rudder cable to TCB RC Output 1 and the DMD Throttle cable to TCB RC Output 2. But because the DMD has a built-in BEC remember to remove the center wire from the servo plugs first!
You can also use the other two channels on the DMD for turret motors although the TCB has built-in turret motor controllers so they are not really necessary.
Because the DMD takes care of mixing the TCB's various Turn Modes will not work and are disabled. The DMD does allow neutral turns (spin turns) but the process is slightly different from the TCB behavior, the DMD performs spin turns under ~50% throttle when the steering is held all the way to the left or right (by comparison the TCB performs neutral turns when throttle is zero and steering is applied).
Tamiya has several brushed ESCs designed to be used with their RC cars that could also work with the TCB, these include the TEU-101BK, TEU-104BK, and the TEU-105BK. All are rated to 60 amps but the 104 and 105 both limit power in the reverse direction to 50%. All three operate at 1 kHz frequency which is extremely loud and annoying. All of them, even the ones that say “no BEC” still must have the center pin of the signal cable removed before attaching to the TCB.
The cheapest you could find these ESCs would be roughly $25-$30 each, meaning more than double the price of using XCars and conceivably even more than the far superior Sabertooth 2×5. So they are not recommended, but we mention them because many people who also build Tamiya RC cars may have several of these ESCs on hand, and if so, feel free to use them.
Hobbywing Quicrun 1060
The Hobbywing Quicrun 1060 brushed speed controller is ubiquitous on AliExpress, Banggood, eBay, Amazon and even HobbyKing sells a variant. It is rated to 60 amps peak at up to 3S lipo input voltage. It is quite cheap, usually in the range of $20 USD, although versions with a fan or those that are waterproof (“WP” version) go for more. Be sure to put them in “F/R” mode (forward reverse with no brake).
Don't Forget! You MUST disable the BEC on the speed controller before attaching it to the TCB!