Number of same value

3

2

1

3

1

1

2

1

2

1

1

5

1

2

4

0

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

5

1

0

1

1

1

2

2

1

1

3

1

1

1

1

1

1

2

1

0

1

1

2

4

1

5

1

1

1

1

1

1

1

1

Combined Modulator/Demodulator Parts List

(Shopping List)

Print shopping list

Quantity - Value or part number

1 - 220pF (mica or metallized film) 
1 - 270pF (mica or metallized film)
1 - 2200pF (mica or metallized film)
3 - .001uF (metallized film)
1 - .001uF (2% polypropylene)
3 - .01uF (metallized film)
1 - .05uF (ceramic)
8 - .1uF (ceramic)
7 - 1uF (35v tantalum)
2 - 4.7uF (25v electrolytic)
2 - 10uF (25v electrolytic)
2 - 100uF (16v electrolytic)
1 - 270uF (16v electrolytic)
1 - 10pF (ceramic)

1 - API PDB-C142 (Digikey PDB-C142-nd) Photodiode 

1 - 1/8 inch stereo phone jack

2 - 1N914 (1N4148) diode 
2 - 1N5817 (Schottky rectifier)

1 - 4.7mH (molded choke)

1 - 2N2222 transistor

1 - Laser diode (Cheap laser pointer)

(all resistors are 5% 1/4 watt except where noted) 

1 - 2 Ohm
1 - 10 Ohm
1 - 240 Ohm
1 - 470 Ohm
1 - 560 Ohm
2 - 1k 
2 - 2.2k
1 - 9.53k (1% 1/4-Watt)
10 - 10k 
3 - 33k
8 - 100k
2 - 270k
1 - 820k
2 - 1M

1 - 500 Ohm (trimpot)
3 - 10k (trimpot)
1 - 100k (trimpot)
1 - 10k (Audio taper pot - chassis mount)

2 - LF347 (Quad JFET opamp)
2 - CD4069 (Hex CMOS inverter)
2 - CD4013 (Dual CMOS D flip-flop)
1 - LM386-4 (Audio amp.)
1 - TC1411 (HS driver) (Digikey TC1411CPA-nd)
1 - LM317 (Voltage regulator)

1 - modulator printed circuit board
1 - detector/demodulator printed circuit board

2 - male/female circuit bd power supply connectors (if used)* (user selected)
1 - male/female laser diode connector (if used)* (user selected)
1 - male/female detector diode connector and cable (if used)* (user selected)

*The power, laser and photodiode connections can be made by directly soldering to the circuit boards, without connectors, if you like.

Closing notes:

• Remember that the "bigfoot" format is a surface mount layout - no holes. The copper traces are etched on the top side of the board.
• The traces should be etched on double-sided copper-clad blank PC board material, with the lower side masked off with masking tape or electrical tape and left un-etched. The lower side copper should be connected to the grounded, negative power rail (the lower side copper acts as a shield).
• A common way to make printed circuit boards at home is the iron-on toner transfer process. That process requires the mirror image versions of the PCB trace images above. More information on the iron-on process can be found by Googling "iron on pcb".
• All of the components are installed on the top side. The components are all standard axial- or radial-leaded devices. (The format is very forgiving of variations in component size and style.) The integrated circuits are all standard DIP-package devices.  Bend the DIP pins outward before soldering to the board.

Here's what it's supposed to look like:

PCB layouts courtesy John West, KB0ONB, [email protected] (kay bee zero oh en bee)