Connecting two separate battery negatives together ???

[collectors]

Hi, i have an RC receiver board & a FET buffer board / switch. Both boards have a separate battery supply. 1 is 12v & the other is 6v. It says connect both battery's on the negative side. Is this OK?, or do i need to separate some how. Thanks

 

[bertus]

Hello,

Do you have details on the fet board?
Wich other boards do you have?
You can connect all negative lines together.

Bertus

 

[collectors]

Hello,

Do you have details on the fet board?
Wich other boards do you have?
You can connect all negative lines together.

Bertus

Hi, its all for an RC model train & i have a receiver fitted to the train with spare "2 low outputs & 1 high output". It was said to connect the FET to the low output so i could switch some lights as the low outputs on the receiver are not strong enough to do this. I might even have the FET switching a relay depending on how many lights..

 

[bertus]

Hello,

Do you have details on the receiver, as I do not understand the "2 low ouputs and 1 high output" statement?
A datasheet would very much help.

Bertus

 

[Harald Kapp]

You must connect the battery negatives together to create a common reference potential. If you don't do this, your receiver's output (connected to the driver's input) will be floating, there will be no path for current from the receiver to flow into the driver and back to the receiver. This will lead to non-predictable, erratic behavior of the whole circuit.