Elenco Projects 102-305 - Manual (Page 6)

MORE Advanced Troubleshooting
(Adult supervision recommended)
Elenco ® is not responsible for parts damaged due to incorrect
wiring.
If you suspect you have damaged parts, you can follow
this procedure to systematically determine which ones
need replacing:
1. - 9. Refer to project manual 1 (projects 1-101) for testing steps
1-9, then continue below. Test both lamps (L1, L2) and
battery holders in test step 1, all blue snap wires in step 3,
and both LEDs (D1, D2) in step 5.
10. 1K Ω (R2), 5.1K Ω (R3), and 10K Ω (R4) resistors: Build
project #7 but use each of these resistors in place of the 100 Ω
resistor (R1), the LED should light and the brightness
decreases with the higher value resistors.
11. Antenna (A1): Build the mini-
circuit shown here, you should
hear sound.
12. NPN transistor (Q2): Build the
mini-circuit shown here. The
LED (D2) should only be on if the
press switch (S2) is pressed. If
otherwise, then the NPN is
damaged.
13. PNP transistor (Q1): Build the
mini-circuit shown here. The
LED (D1) should only be on if the
press switch (S2) is pressed. If
otherwise, then the PNP is
damaged.
14. Adjustable resistor (RV): Build project #261 but use the 100 Ω
resistor (R1) in place of the photoresistor (RP), the resistor
control can turn the LED (D1) on and off.
15. 100 Ω K resistor (R5) and 0.02 μ F (C1), 0.1 μ F (C2), and 10 μ F
(C3) capacitors: Build project #206, it makes sound unless
the resistor is bad. Place the 0.02 μ F capacitor on top of the
whistle chip (WC) and the sound changes (pitch is lower).
Replace the 0.02
μ F with the 0.1 μ F and the pitch is even lower.
Replace the 0.1 μ F with the 10 μ F and the circuit will “click”
about once a second.
16. 100 μ F (C4) and 470 μ F (C5) capacitors: Build project #225,
press the press switch (S2) and turn on the slide switch (S1).
The LED (D1) should be lit for about 15 seconds then go out
(press the press switch again to reset this). Replace the 470
μ F
with the 100 μ F and the LED is only lit for about 4 seconds now.
17. Power Amplifier IC (U4): Build project #293, the sound from
the speaker (SP) should be loud.
18. Microphone (X1): Build project #109, blowing into the
microphone should turn off the lamp (L2).
19. Variable Capacitor (CV): Build project #213 and place it near
an AM radio, tune the radio and the capacitor to verify you hear
the music on your radio.
20. High Frequency IC (U5): Build project #242 and adjust the
variable capacitor (CV) and adjustable resistor (RV) until you
hear a radio station.
Note: If you have the more advanced Models SC-500 or SC-750,
there are additional tests in your other project manuals.
ELENCO ®
150 Carpenter Avenue
Wheeling, IL 60090 U.S.A.
Phone: (847) 541-3800
Fax: (847) 520-0085
e-mail: [email protected]
Web site: www.elenco.com
You may order additional / replacement parts at:
www.snapcircuits.net
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