Making Electronics

To control solenoid valve I used a famus and popular electronic timer NE555. It is extremely easy to build.
It has two potentiometers to control valve opening and closing times. Setting these values allows to obtain any Rate Of Fire.
Also the System has a Full-Auto and Semi-Auto jumper to choose fire type option. The LED diode inform when system is working.


NE555 parts for fire control unit picture

   NE555 Timer and other electronics parts for fire control unit.


Electronics Schematic Layout

    Schematic Layout

Click to Download Hi-Resolution plans



Parts List:

At first go to the shop to gather some electronic components.

No. Quantity Name Value
1 1 PCB Board -
2 1 Timer NE555 -
3 1 LED Diode -
4 1 Jumper and PINs -
5 1 Transistor BD233
6 2 Diode IN4007
7 1 Capacitor 2.2uF 50V
8 2 Potentiometer 200k
9 1 Resistor 4.7k Ohm
10 1 Resistor 50M Ohm
11 1 Resistor 2k Ohm
12 2 Connector -

NE555 Timer - Assembled unit and ready to work picture

   NE555 Timer - Assembled unit and ready to work.


NE555 Calculator Info picture

   NE555 Calculator: click here to download | Go to Program Website


AEG to HPA - Control Unit Box picture 1

   Control Unit Box - external view.


AEG to HPA - Control Unit Box picture 2

   Control Unit Box - inside view.



Second Step - Shooting Mechanism

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