"Hello, I have the sabertooth 2x25.

I am using it on 24v batteries to power two motors they have been connected and my hope is that one stick on the radio control controls foward back left right I have he DX6i with a Spectkrum AR6210 receiver,

I have checked all the connections are in the correct way and the DIP wizard was used with the ONE and FIVE in position.

I have checked with a small servo to ensure the transmitter is correct when I connected it all together, I dont get any response it doesnt move.

Can you tell me how to test to see if the controller is faulty.

Hoping a swift response."

– richard

"Re. sabretooth 25amp speed controler

Dear Sir, further to our phone conversation About the possibility of using this controller For my toylander, I read the item description To which it did state that this controller is
possible to reverse If so that’s fine, but I did also read about the weight of the robot
or such that it would power being only 50 kg, a fully laiden toylander is 105 kgs ie batteries
ect (with no people) is this relevant at all, the motors I am using are fracmo pm25450 12 volt
rated at 75 watts min 160 watts max, many thanks for the info so far.
ps my email is ...
"

– peter cridge

"You need nothing more than a resistor between the PICAXE output and the Sabertooth analogue input and a capacitor between the Sabertooth analogue input and the common ground connection.

The resistor and capacitor values will need calculating or if you have a scope, trial and error works as well.

The PWM output has a frequency that you set in the PICAXE software, it's the duty cycle that changes. The RC circuit averages these pulses out to give a smooth voltage. Too much and the speed response will be sluggish or even result in gross inaccuracies in the averaged voltage.

The time constant of the resistor / capacitor circuit should be about 100 times that of the period of the PWM frequency. So for example, if you set the PWM to 1khz which is 1ms, then your CR circuit time constant should be 100mS.

The CR time constant is simply the resistor value in Ohms x the capacitor value in Farads. So, continuing the example for 100mS, chooses a capacitor first, say 0.47uF, then R=100mS/0.47uF = 212k or the nearest preferred value to it.

That resistor value is higher than I would suggest, so choose a larger capacitor and re-calculate but of course this all depends on your PWM frequency.

We would recommend a PWM frequency of 4kHz, this allows the duty cycle to be set 0-1000 (i.e. 0-100.0%) giving the best possible fine resolution.

Hope that helps you."

– Admin

"The Sabertooth has a number of input modes to set the speed. These are:

1. Analogue input
2. RC input
3. Simplified serial input
4. Packetized serial input

With respect to the PICAXE 28
1. The PICAXE does not have a direct analogue output but it is very easy to use the PWM output and a CR circuit to generate an analogue voltage and is the method we would recommend.
2. The PICAXE has a servo command output that can directly drive the Sabertooth in RC mode. We have found that the 28X1 has an issue with the servo command when also used with the I2C command , otherwise it is fine.
3&4. The PICAXE has serial output commands that can drive the Sabertooth serially.

So the answer to your question, yes and in three possible ways."

– Admin