Airsoft MOSFET Unit

Immediate reaction for the trigger, no burnt contacts.

The omission of mechanical contacts and replace them with electronic transistor is one of the first things to do with airsoft replica.

Gearbox connection picture

   Default gearbox connection diagram.


MOSFET connection picture

   MOSFET connection diagram.



First Step - Electronics

MOSFET and Resistors picture

   IRF3205 and resistors.


There are many transistors which can be used. I chose IRF3205 N-CHANNEL MOSFET. All specification is in manufacturers Datasheet PDF.
Basic parameters: 55V 110A 0,008R.
If this transistor is unavailable, choose another. Note that amperage should be as high as possible, and Volts over 30V for typical airsoft battery-powered guns.

At the beginning you should soldered resistor to the GATE and SOURCE legs of the transistor.

MOSFET Instalation picture

   IRF3205 MOSFET and Resistor 30k Ohm instalalled.



To the GATE legs soldering the 100 Ohm transistor. To the end of the resistor solder wire, as shown below. End of the cable will be connected to the trigger. Control cable is ready.

Control Cable connection picture

   100 Ohm resistor and Control Cable.



To the DRAIN legs soldering the wire. End of the wire soldering to the MINUS (-) motor contact. Use the black cable.
Next connect PLUS (+) battery contact to PLUS (+) motor contact. And batery PLUS connect to the second trigger pin. Only one will be free, The second we connected earlier. At this point, the system is almost ready.


Adjust the cable length as is needed and if necessary replace it. At the end, make sure that no defective connections. If necessary use isolation tapes.