Instruction manual

SM100 • 12
 18. Install R4, 1K ohm (brown-
black-red).
 19. Install R1, 10 ohm (brown-
black-black).
 20. Locate and install Q1, a
2N3904 transistor. Transistors
have three "legs" and must be
mounted correctly. Notice that the part contains a "flat" side with the
writing imprinted on it. Be sure to follow the parts diagram for correct
placement. To install, slide the center legs through the circuit board and
push the component as close to the board as possible without "straining"
the leads. Solder all three connections securely.
 21. Install Q2, another 2N3904 transistor. Be sure to orient it as shown in
the parts diagram.
 22. From the scrap component leads you've been saving, form and
install “jumper” wire JMP1 on the circuit board. Jumper wires act like
electronic “bridges” that carry signals over the printed circuit traces
underneath.
 23. Install C2, .1 uF disc capacitor.
 24. Install R5, 470 ohm (yellow-violet-brown).
 25. Install L1, 1800 uH inductor (green cylinder marked 182). This
component allows the DC voltages to pass through it, but it “chokes” off
the high frequency radio waves and prevents them from getting into your
power supply circuit.
Whew! You’ve just completed the entire power supply portion of you signal
magnet antenna.
Next, we’ll move on to the antenna board. Before you go any further, we
suggest that you look over your work. Try to identify and correct any cold
soldering connections, solder bridges and incorrectly installed parts.
 28. Install R16, 1M ohm resistor (brown-black-green). R16 is used to
set the proper bias voltage on Q5.
 29. Install C13, .01 uF capacitor (marked .01 or 103 or 10 nF).
 30. Install C11, .1 uF capacitor (marked .1 or 104). C11 and C13 are
used to pass the AC signal without passing DC current.
PC Board
LED
Leave these leads
as long as possible
(+)
(-)