Have you ever dreamt of becoming a marksman? I can help you! You need a laser pointer, few electronic parts, some trash and 3-4 hours. The target can be stationary and moveable. You can practice as much shooting as you like. Let’s come to the point.
Step 1: Materials and Tools
1 milk carton (for a target)
1 shampoo bottle (for a gun’s barrel)
1 body deodorant enclosure (for a gun’s grip)
color paper (to make a mask and decorate a target)
blister (to shield LEDs )
thread (to hang a target)
double-sided adhesive tape
a laser pointer
4 small bolts with nuts (washers are optional)
For a laser gun – a 2200mF/10V capacitor, a press on/off switch(for a trigger), a 3AA battery holder, a 3V buzzer (with in-built generator), a small switch (to activate a buzzer).
For a target – 1 PNP germanium transistor, 1 NPN transistor (BC547), 1 resistor 1K3/0,25W, 1 speaker 8 Ohm/0,25W, 2 LEDs(red/3mm), 1AA battery holder, a small switch, a phototransistor.
Step 2: Target schematic
The schematic is a modified RL-oscillator. I added 2 LEDs and a phototransistior. Note: it is important to use LEDs with the lowest working voltage (under 2V). You cannot substitute a germanium transistor with a silicon one.
Step 3: Target's electronic work
You needn’t a PCB. Solder transistors, a resistor and wires to the speaker’s lead-outs. When you are done, test the target. As soon as you expose the phototransistor to the light the LEDs will be on and the speaker starts beeping.
Step 4: Mask
I am fond of origami. If you don’t want to be bothered with folding you can draw a picture then cut it out and paste on a piece of cardboard. Punch holes in the eyes to install LEDs. Punch a few holes on the nose just opposite the speaker. Punch holes in the mouth to install a small switch. Punch holes in the bowtie to install a phototransistor.