| Part | Total Qty. | Description | Substitutions |
| C1, C2 | 2 | 0.1uf Ceramic Disc Capacitor | |
| C3 | 1 | 100uf 25V Electrolytic Capacitor | |
| R1 | 1 | 100K Ohm 1/4W Resistor | |
| R2 | 1 | 1M Ohm 1/4W Resistor | |
| R3 | 1 | 10K Pot | |
| Q1 | 1 | NPN Phototransistor | |
| U1 | 1 | 741 Op Amp | |
| U2 | 1 | LM386 Audio Amp | |
| SPKR1 | 1 | 8 Ohm Speaker | |
| T1 | 1 | 8 Ohm:2K Audio Transformer | |
| MISC | 1 | Wire, Board, Knob For R3, LASER Tube and Power Supply |
- In the transmitter schematic, no ballast resistor is shown because most small LASER power supplies already have one built in. Yours may differ, and a resistor may be needed.
- The receiver should be kept away from bright lights. You may want to put a piece of wax paper in front of Q1 to keep the LASER from swamping it.
- In order to get any decent amount of modulation, you may need to drive T1 with more then a watt.
- The circuit can be made to transmit computer data with the use of two modem chips.
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