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46. Install R29, a 10K resistor [brown-black-orange]. Mount this
resistor standing up too, please. It is located next to U3.
47. Install R30, a 470 ohm resistor [yellow-violet-brown] standing up.
48. Install R31, a 470 ohm resistor [yellow-violet-brown] standing up.
49. Install R16, a 47K ohm resistor [yellow-violet-orange] not sitting, but
standing. It is located next to U1.
50. Install R17, a 2.2K ohm resistor [red-red-red] standing.
51. Install C7, a .1uF disc capacitor [marked .1 or 104].
52. Identify R15, a 5K ohm potentiometer. It will be small, orange, and
marked "502." Press the potentiometer flush with the board and solder
all three connections. This part will let you adjust the pitch of the tone.
53. Install D10, a 1N4148 glass bead diode, paying particular attention
to the way that the band is pointing.
You have now completed the circuit that makes the tone that you hear. Now
let's move on and make the circuit that amplifies the tone so that you can
hear it. (Don't forget to save your component leads. You are going to need
them soon!)
54. Install R13, a 10K ohm resistor [brown-black-orange].
55. Install C6, a .1uF disc capacitor [marked .1 or 104].
56. Install Q2, a 2N3904 NPN transistor. Make sure the flat side is
oriented correctly.
57. Install Q1, a 2N3904 NPN transistor. Make sure that the flat side is
oriented correctly. The part will be located near the miniature jacks.
58. Install R9, a 47K ohm resistor [yellow-violet-orange]. You may note
that this resistor needs to be standing also.
59. Insert R12, a 47 ohm resistor [yellow-violet-black] standing up.
60. Install C18, a .01uF disc capacitor [marked .01 or 103 or .01uF].
61. Install D5, a 1N4002 diode. This diode will be black, and have a
stripe at one end. Just as with other diodes, make sure the stripe
matches up with the board.
You have just finished the part of your keyer that makes it such a great code
oscillator not including the speaker. With this feature, you can not only
practice, but help to teach your friends about the wonderful world of CW!
We'll just make a few more finishing touches and then move on to the power
supply!
CW700 • 16
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