How to Step Down from 8.4v to 6v for Different Servos?

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WickedFog

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I just realized I have an 8.4v capable steering servo, but a shift servo that can only handle up to 6v. I have never ran into this problem before 🤔

So how do I only send 6v to one servo if I use a BEC set to 8.4v? I assume a resistor or something? I don't really know crap about electronics when it comes to this stuff, so any help would be appreciated.
 
I just realized I have an 8.4v capable steering servo, but a shift servo that can only handle up to 6v. I have never ran into this problem before 🤔

So how do I only send 6v to one servo if I use a BEC set to 8.4v? I assume a resistor or something? I don't really know crap about electronics when it comes to this stuff, so any help would be appreciated.
Whats your setup...all of it?
 
whatever voltage is esc going to run on Id use that as main ..along with rx.. you can buy a ubec to supply either voltage just have to look.. you can take signal wire and run it straight to whatever channel in rx it is on.. you can hardwire ubec to servo to power it..if you want I can help you step by step Ill send you my phone # to walk you thru this if needed.
 
Tekin RX4, Tekin ROC412 HD 2300kv, Tekin T440 servo #8.4v, Hitec HS-70MG @6.0v, Castle 10A BEC.
whatever voltage is esc going to run on Id use that as main ..along with rx.. you can buy a ubec to supply either voltage just have to look.. you can take signal wire and run it straight to whatever channel in rx it is on.. you can hardwire ubec to servo to power it..if you want I can help you step by step Ill send you my phone # to walk you thru this if needed.
I was gonna tag you in this because I figured you'd know. I will PM you in a bit. The ESC will only go to 7.4v I believe.
 
You could run the larger 8.4V servo directly off of the CC BEC and the smaller 6v off the rx with the ESC internal BEC.
Basically all you would be doing is making use of the RX4's BEC.
That is what I was thinking. If I use the internal BEC set to 6v and run that to the receiver as normal. Then take the signal wire from the receiver channel #1 and the power wires from the external BEC to the steering servo, would that do it?
 
Please keep in mind I was explained this to by someone but have never done it personally.
Connect the red and black wires off the bec directly to the red and black wires on the 8.4v servo. Then connect signal wire from the 8.4 servo to the rx.
It does seem correct but I would double check with someone who has more knowledge.
I hope you get it sorted:thumbs-up:
 
Please keep in mind I was explained this to by someone but have never done it personally.
Connect the red and black wires off the bec directly to the red and black wires on the 8.4v servo. Then connect signal wire from the 8.4 servo to the rx.
It does seem correct but I would double check with someone who has more knowledge.
I hope you get it sorted:thumbs-up:
Yeah, that is what I gather from what TNT said and doing a little research. It makes sense.

For the time being, I am just setting the internal BEC to 6v and finishing the build because I am not even sure where just the standard wiring is going to route in this Ryft kit. The cage is the chassis, but the motor, ESC, and servos are mounted to the transmission and front axle. But the receiver mounts in the mockup fuel cell in the back of the cage. So to remove the "body" means removing 10 screws, unhooking the top of the shocks (so 4 more screws), and disconnecting all the plugs from the receiver. But I have to wait to finish this build this coming weekend so we can put the vid on my son's channel 😜

Thanks for the help guys!
 
OK, is this correct? If I just use a female JR cable and splice into this, it becomes plug-n-play.
Dual-Servo-Voltages-Setup.png
 
Dammit. Mine has a white wire not a blue one. This won’t work for me.
LOL. How did I know someone was going to mention that? White wouldn't show up on the background 🤣
 
Yeah, that is what I gather from what TNT said and doing a little research. It makes sense.

For the time being, I am just setting the internal BEC to 6v and finishing the build because I am not even sure where just the standard wiring is going to route in this Ryft kit. The cage is the chassis, but the motor, ESC, and servos are mounted to the transmission and front axle. But the receiver mounts in the mockup fuel cell in the back of the cage. So to remove the "body" means removing 10 screws, unhooking the top of the shocks (so 4 more screws), and disconnecting all the plugs from the receiver. But I have to wait to finish this build this coming weekend so we can put the vid on my son's channel 😜

Thanks for the help guys!
Dig the Ryft build you got going on! :thumbs-up:
 
Dig the Ryft build you got going on! :thumbs-up:
Thanks. It is one awesome kit. Outside of the electronics giving me nothing but fits, it has been a great build.
 
OK, is this correct? If I just use a female JR cable and splice into this, it becomes plug-n-play.
View attachment 143709
The power to the rx has to come from the esc...so the blue wire has to go to the steering port which is channel 3...?
can't have power from esc AND BEC going to the rx is what I'm getting at.
 
The only power going to the Rx is the green wire (channel 2 in my diagram). The blue wire is just a signal wire from channel 1 to the steering servo. You might have to zoom in to see it, but blue is only connected to signal pin. Green represents the ESC to Rx cable as is.
 
The only power going to the Rx is the green wire (channel 2 in my diagram). The blue wire is just a signal wire from channel 1 to the steering servo. You might have to zoom in to see it, but blue is only connected to signal pin. Green represents the ESC to Rx cable as is.
Right on. :)
I burnt a shift servo and didnt have the patience to figure it out so used a high torque servo for H/L and dig. 🤪😆
 
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