Elenco SC300, SC750 User Manual

Copyright © 2012, 2010 by Elenco®Electronics, Inc. All rights reserved. No part of this book shall be reproduced by 753104 any means; electronic, photocopying, or otherwise without written permission from the publisher.

REV-D Revised 2012

Project 317

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Table of Contents

Basic T roubleshooting 1 Parts List 2

About Your Snap Circuits®Parts 3, 4

Advanced T roub leshooting 4

DO’s and DON’Ts of Building Circuits 5 Project Listings 6, 7 Projects 306-511 8 - 61 Other Snap Circuits®Products 62

1. Most circuit problems are due to incorrect assembly. Always double-check that your circuit exactly matches the drawing for it.

2. Be sure that parts with positive/negative markings are positioned as per the drawing.

3. Be sure that all connections are securely snapped.

4. Tr y replacing the batteries.

5. If the motor spins but does not balance the fan, check the black plastic piece with three prongs on the motor shaft. Be sure that it is at the top of the shaft.

Elenco

is not responsible for parts damaged due to

incorrect wiring.

Basic T roub leshooting

Note: If you suspect you have damaged parts, you can

follow the Advanced Troubleshooting procedure on page 4 to determine which ones need replacing.

Review of How To Use It (See page 3 of the Projects 1-101 manual for more details.)

The Snap Circuits®kit uses building blocks with snaps to build the different electrical and electronic circuits in the projects. These blocks are in different colors and have numbers on them so that you can easily identify them. The circuit you will build is shown in color and with numbers, identifying the blocks that you will use and snap together to form a circuit.

Next to each part in every circuit drawing is a small number in black. This tells you which level the component is placed at. Place all parts on level 1 first,

then all of the parts on level 2, then all of the parts on level 3, etc.

A large clear plastic base grid is included with this kit to help keep the circuit block together. The base has rows labeled A-G and columns labeled 1-10.

Install two (2) “AA” batteries (not included) in the battery holder (B1). The 2.5V and 6V bulbs come packaged separate from their sockets. Install the 2.5V bulb in the L1 lamp socket, and the 6V bulb in the L2 lamp socket.

Place the fan on the motor (M1) whenever that part is used, unless the project you are building says not to use it.

Some circuits use the red and black jumper wires to make unusual connections. Just clip them to the metal snaps or as indicated.

Note: While building the projects, be careful not to accidentally make a direct connection across the battery holder (a “short circuit”), as this may damage and/or quickly drain the batteries.

WARNING: SHOCK HAZARD -

Never connect Snap Circuits®to the electrical outlets in your home in any way!

WARNING FOR ALL PROJECTS WITH A SYMBOL

Moving parts. Do not touch the motor or fan during operation. Do not lean over the motor. Do not launch the fan at people, animals, or objects. Eye protection is recommended.

WARNING: CHOKING HAZARD-

Small parts. Not for children under 3 years.

Batteries:

• Use only 1.5V AA type, alkaline batteries (not included).

• Insert batteries with correct polarity.

• Non-rechargeable batteries should not be recharged. Rechargeable batteries should only be charged under adult supervision, and should not be recharged while in the product.

• Do not mix alkaline, standard (carbonzinc), or rechargeable (nickel-cadmium) batteries.

• Do not mix old and new batteries.

• Remove batteries when they are used up.

• Do not short circuit the battery terminals.

• Never throw batteries in a fire or attempt to open its outer casing.

• Batteries are harmful if swallowed, so keep away from small children.

• Do not connect batteries or battery holders in parallel.

WARNING: Always check your wiring before

turning on a circuit. Never leave a circuit unattended while the batteries are installed. Never connect additional batteries or any other power sources to your circuits. Discard any cracked or broken parts.

Adult Supervision: Because children’s abilities

var

y so much, even with age groups, adults should exercise discretion as to which experiments are suitable and safe (the instructions should enable supervising adults to establish the experiment’s suitability for the child). Make sure your child reads and follows all of the relevant instructions and safety procedures, and keeps them at hand for reference.

This product is intended for use by adults and children who have attained sufficient maturity to read and follow directions and warnings.

Never modify your parts, as doing so may disable important safety features in them, and could put your child at risk of injury.

-2-

Qty. ID Name Symbol Par t # Qty. ID Name Symbol Par t #

r 3

2-Snap Wire 6SC02

r 1

Analog Meter 6SCM2

r 1

5-Snap Wire 6SC05

r 1

SCR 6SCQ3

r 1

Diode 1N4001

6SCD3

r 1

Relay 6SCS3

r 1

7-Segment LED Display

6SCD7

r 1

Transformer 6SCT1

r 1

FM Module 6SCFM

r 1

Recording Integrated Circuit

6SCU6

You may order additional / replacement parts at our website: www.snapcircuits.net

Note: There are additional part lists in your other project manuals. Part designs are subject to change without notice.

Important: If any parts are missing or damaged, DO NOT RETURN TO RETAILER. Call toll-free (800) 533-2441 or e-mail us at:

help@elenco.com. Customer Ser vice • 150 Car penter Ave. • Wheeling, IL 60090 U.S.A.

Parts List (Colors and styles may vary) Symbols and Numbers

-3-

(Part designs are subject to change without notice). The FM module (FM) contains an integrated FM radio circuit.

Refer to the figure belo

w for the pinout description:

The meter (M2) is a very important indicating and measuring device

. You’ll use it to measure the amount of current or voltage depending on the circuit configuration. Notice the meter has a “+” sign, indicating the positive terminal (+ power from the batteries). The other snap is the negative terminal (– power return to batteries). The meter has a switch to change between scales, indicated as LOW and HIGH (or 10mA and 1A).

The recording IC module (U6) contains an integrated recording circuit.

You can record a message up to five seconds long. There are also three pre-recorded songs. Ref er to the figure below f or the pinout descriptions:

The relay (S3) is an electronic switch with contacts that can be closed or opened. It contains a coil that gener

ates a magnetic field when current flows through it. The magnetic field attracts an iron armature, which switches the contacts (see figure).

The transformer (T1) consists of two coil windings on one core. One coil is called the Primar

y (input) and the other the Secondary (output). The purpose of the transformer is to increase the amount of AC voltage applied to the primary. This transformer is a step-up transformer.

Diode (D3) - Think of a diode as a one-way valve that permits

current flow in the direction of the arro

w. The anode (arrow) is the positive side, and the cathode (bar) is the negative. The diode conducts or turns on when the voltage at the anode is 0.7V or greater.

About Your New Snap Circuits®Parts (Note: There is additional information in your other project manuals).

(+)

OUT(–)

FM Module:

(+) - power from batteries (–) - power return to batteries T - tune up R - reset OUT - output connection

See project #307 for example of proper connections.

(+)

OUT

(–)

Recording IC Module:

(+) - power from batteries (–) - power return to batteries RC - record Play - play OUT - output connection Mic + - microphone input Mic – - microphone input

See project #308 for example of proper connections.

RCPlay

Mic –

Mic +

COM

Relay:

Coil - connection to coil Coil - connection to coil NC - normally closed contact NO - normally open contact COM - Common

See project #341 for example of proper connections.

Coil

CTB

Transformer:

A - less windings side A - less windings side B - more windings side B - more windings side CT - center tap

See project #347 for example of proper connections.

Anode

Diode:

Anode - (+) Cathode - (–)

Cathode

(+)

(–)

Meter:

(+) - power from batteries (–) - power return to batteries

Less Windings

More Windings

Our Student Guides give much more information about your parts, along with a complete lesson in basic electr onics. See www .snapcir cuits.net/learn.htm or page 62 for more inf ormation.

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 - 20. Refer to project manuals 1 & 2 (projects #1-101, #102-305) for testing steps 1-20, then

continue belo

21. FM Module (FM): Build project #307, you should hear FM radio stations.

22. Meter (M2): Build the mini-circuit shown here and set the meter switch to LOW (or 10mA), the meter (M2) should deflect full scale

. Then, replace the 10kΩ resistor (R4) with the 2.5V lamp (L1), and set the meter switch to HIGH (or 1A). The meter should deflect to 1 or higher.

23. Recording IC (U6): Build project #308. Make an 8 second recording, then listen to the three prerecorded songs

24. Relay (S3): Build project #341. The red LED (D1) should be on when the slide switch (S1) is on, and the green LED (D2) should be on when the s

witch is off.

25. Transformer (T1): Build the mini-circuit shown here. Pressing the press switch (S2) flashes the green LED (D2). Connect the jumper wire to the CT point. Pressing the press switch flashes the green LED.

26. Diode (D3): Build the mini-circuit shown here, the red LED (D1) should light. Re

verse the direction of the diode, the LED should not light now.

27. SCR (Q3): Build the mini-circuit shown here. Turn on the slide switch (S1) and the motor (M1) should not spin.

Press the press switch (S2), the motor should start spinning. Now turn the slide switch off and on, the motor should not spin.

28. 7-Segment Display (D7): Build project #337. All segments light, displaying the number 8.

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SCR (Q3) - An SCR is a three-pin (anode, cathode

and gate) silicon-controlled rectifier diode. Like a standard diode, it permits current flow in only one direction. It will only conduct in the f orw ard direction when triggered by a short pulse (or steady voltage applied) between the gate and cathode terminals.

A high current may damage this part, so the current must be limited by other components in the circuit.

The 7-segment display (D7) is found in many devices today. It contains 7 LED’s that have been combined into one case to make a convenient device for displa ying n umbers and some letters. The display is a common anode version. That means that the positive leg of each LED is connected to a common point which is the snap marked “+”. Each LED has a negative leg that is connected to one snap. To make it work you need to connect the “+” snap to positive three volts. Then to make each segment light up, connect the snaps of each LED to ground. In the projects, a resistor is always connected to the “+” snap to limit the current.

A high current may damage this part, so the current must be limited by other components in the circuit.

SCR:

A - Anode K - Cathode G - Gate

7-segment Display:

(+) - power from batteries A - Segment A B - Segment B C - Segment C D - Segment D E - Segment E F - Segment F G - Segment G DP - Decimal Point

See project #337 for example of proper connections.

Advanced Troubleshooting (Adult super vision recommended)

About Y our Snap

Circuits

Parts (continued)

-5-

DO’s and DON’Ts of Building Circuits

After building the circuits given in this booklet, you ma y wish to e xperiment on your own. Use the projects in this booklet as a guide, as many important design concepts are introduced throughout them. Every circuit will include a power source (the batteries), a resistance (which might be a resistor, lamp, motor, integrated circuit, etc.), and wiring paths between them and back. You must be careful not to create “short circuits” (very low-resistance paths

across the batteries

, see examples below) as this will damage components and/or quickly drain your batteries. Only connect the IC’s using configurations given in the projects,

incorrectly doing so may damage them. Elenco®is not responsible for parts damaged

due to incorrect wiring.

Here are some important guidelines:

ALWAYS

USE EYE PROTECTION WHEN EXPERIMENTING ON YOUR OWN.

ALWAYS

include at least one component that will limit the current through a circuit, such as the speaker, lamp, whistle chip, capacitors, IC’s (which must be connected properly), motor, microphone, photoresistor, or fixed resistors.

ALWAYS

use the 7-segment display, LED’s , transistors, the high frequency IC, the SCR, the antenna, and switches in conjunction with other components that will limit the current through them. Failure to do so will create a shor t circuit and/or damage those parts.

ALWAYS

connect the adjustable resistor so that if set to its 0 setting, the current will be limited by other components in the circuit.

ALWAYS

connect position capacitors so that the “+” side gets the higher voltage.

ALWAYS

disconnect your batteries immediately and check your wiring if something appears to be getting hot.

ALWAYS

check your wiring before turning on a circuit.

ALWAYS

connect IC’s, the FM module, and the SCR using configurations given in the projects or as per the connection descriptions for the parts.

NEVER

try to use the high frequency IC as a transistor (the packages are similar, but the parts are different).

NEVER

use the 2.5V lamp in a circuit with both battery holders unless you are sure that the voltage across it will be limited.

NEVER

connect to an electrical outlet in your home in any way.

NEVER

leave a circuit unattended when it is turned on.

NEVER

touch the motor when it is spinning at high speed.

Note: If you have the more advanced Model SC-750, there are additional guidelines in your other project manual.

For all of the projects given in this book, the parts may be arranged in diff erent ways without changing the circuit. For example, the order of parts connected in series or in parallel does not matter — what matters is how combinations of these sub-circuits are arranged together.

Examples of SHORT CIRCUITS - NEVER DO THESE!!!

You are encouraged to tell us about new circuits you create. If they are unique, we will post them with your name and state on our website at www.snapcircuits.net/kidkreations.htm. Send your suggestions to Elenco

Elenco®provides a circuit designer so that you can make your own Snap Circuits®drawings. This Microsoft®Word document can be downloaded from www.snapcircuits.net/SnapDesigner.doc or through the

www.snapcircuits.net web site.

WARNING: SHOCK HAZARD - Nev

er connect Snap Circuits®to

the electrical outlets in your home in any way!

Placing a 3-snap wire directly across the batteries is a SHORT CIRCUIT.

This is also a

SHORT CIRCUIT.

When the slide switch (S1) is turned on, this large circuit has a SHORT CIRCUIT path (as shown by the arrows). The short circuit prevents any other portions of the circuit from ever working.

NEVER

DO!

Warning to Snap Rover owners: Do not connect your parts to the

Rover body except when using our approved circuits, the Rover body has a higher voltage which could damage your parts.

NEVER

DO!

NEVER

DO!

NEVER

DO!

Project # Description Page #

306 AM Radio 8 307 Adjustable Volume FM Radio 8 308 Playback & Record 9 309 Playing Music 9 310 Light-Controlled Music 9 311 Touch-Controlled Music 9 312 Power Playback & Record 10 313 Power Amplified Playing Music 10 314 Power Light-Controlled Music 10 315 Pow er Touch-Controlled Music 10 316 FM Radio 11 317 Mega Circuit 11 318 SCR 2.5V Bulb 12 319 SCR & Motor 12 320 Music Alarm 13 321 Light-Music Alarm 13 322 Light-Controlled SCR 13 323 3mA Meter 14 324 0-3V Meter 14 325 Function of adjustable resistor 15 326 Function of Photoresistor 15 327 Meter Deflect by Motor 16 328 SCR 6V Bulb 16 329 Principle of Segment LED 17 330 Display #1 17 331 Display #2 17 332 Display #3 17 333 Display #4 17 334 Display #5 18 335 Display #6 18 336 Display #7 18 337 Display #8 18 338 Display #9 18 339 Display #0 18

Project # Description Page #

340 Music Meter 18 341 LED & Relay 19 342 Manual 7 Second Timer 19 343 Half Wave Rectifier Circuit 20 344 Half Wave Rectifier Circuit (II) 20 345 LED vs. Diode 20 346 Current & Resistance 20 347 Telegraph 21 348 Mosquito Sound 21 349 Mosquito Sound (II) 21 350 Mosquito Sound (III) 21 351 Touch-Control Mosquito Sound 21 352 Bulb & Relay 22 353 Relay Buzzer 22 354 Transistor Timer 23 355 Light-Controlled Relay 23 356 Bulb Alert Relay 23 357 Adjustable Light Control 24 358 Meter Deflection 24 359 AC to DC Current 25 360 Current Meter 25 361 Buzzer, Relay, & Transformer 26 362 Buzzer & Relay 26 363 Display Capital Letter “F” 27 364 Display Capital Letter “H” 27 365 Display Capital Letter “P” 27 366 Display Capital Letter “S” 27 367 Display Capital Letter “U” 27 368 Display Capital Letter “C” 27 369 Display Capital Letter “E” 27 370 Display “.” 27 371 Display Letter “b” 28 372 Display Letter “c” 28 373 Display Letter “d” 28

Project # Description Page #

374 Display Letter “e” 28 375 Display Letter “h” 28 376 Recorded V oice Transmitter 28 377 Space War Alar m by SCR 29 378 Light Space War Alar m 29 379 Alarm by SCR 29 380 Light & Alarm IC 29 381 Delay Light 30 382 Delay Fan 30 383 Sound Activated Fan 30 384 Recording LED Indicator 31 385 Playback & Record with Meter 31 386 Alarm Light 32 387 Alarm Light (II) 32 388 Night Police Car 33 389 Night Machine Gun 33 390 Night Fire Engine 33 391 Night Ambulance 33 392 Daytime Light Police Car 34 393 Daytime Light Machine Gun 34 394 Daytime Light Fire Engine 34 395 Daytime Light Ambulance 34 396 Flashing 8 35 397 Flashing 8 with Sound 35 398 Musical Space War 35 399 Electronic Noisemaker 36 400 Electronic Noisemaker (II) 36 401 Bee 36 402 Bee (II) 36 403 Bee (III) 36 404 Oscillator Sound 37 405 Oscillator Sound (II) 37 406 Oscillator Sound (III) 37 407 Oscillator Sound (IV) 37

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Project Listings

-7-

Project # Description Page #

408 Oscillator Sound (V) 37 409 Transistor Tester 38 410 Adjustable Voltage Divider 38 411

Automatic Display Capital Letter “C”

412

Automatic Display Capital Letter “E”

413

Automatic Display Capital Letter “F”

414

Automatic Display Capital Letter “H”

415

Automatic Display Capital Letter “P”

416

Automatic Display Capital Letter “S”

417

Automatic Display Capital Letter “U”

418

Automatic Display Capital Letter “L”

39 419 Whistle Chip Sounds 40 420 Whistle Chip Sounds (II) 40 421 Whistle Chip Sounds (III) 40 422 Whistle Chip Sounds (IV) 40 423 Whistle Chip Sounds (V) 40 424 Whistle Chip Sounds (VI) 40 425 LED Music 41 426

Light-Controlled LED Time Delay

41 427

Touch-Controlled LED Time Delay

41 428 Alarm Recorder 42 429 Alarm Recorder (II) 42 430 Machine Gun Recorder 42 431 Time Delay 1-7 Seconds 43 432 Time Delay 43 433 Manual 7 Second Timer (II) 44 434 15 Second Alarm 44 435 Flashing “1 & 2” 45 436 Flashing “3 & 4” 45 437 Flashing “5 & 6” 45 438 Flashing “7 & 8” 45 439 Flashing “9 & 0” 45 440 Flashing “b & c” 46 441 Flashing “d & e” 46 442 Flashing “h & o” 46

Project # Description Page #

443 Flashing “A & J” 46 444

Alar

m Timer 46 445 Alarm Timer (II) 46 446 Alarm Timer (III) 46 447 Bird Sounds 47 448 Bird Sounds (II) 47 449 Bird Sounds (III) 47 450 Bird Sounds (IV) 47 451 Bird Sounds (V) 47 452 Touch-Control Bird Sound 47 453 Motor Sound Recording 48 454 Motor Sound Indicator 48 455 Relay & Buzzer 49 456 Relay & Speaker 49 457 Electronic Playground 49 458 Electronic Cat 50 459 Electronic Cat (II) 50 460 Electronic Cat (III) 50 461 Electronic Cat (IV) 50 462 Buzzer Cat 50 463 Buzzer Cat (II) 50 464 Buzzer Cat (III) 50 465 Lazy Cat 50 466 Meter Deflection (II) 51 467 Automatic Display #1 51 468 Automatic Display #2 51 469 Automatic Display #3 52 470 Automatic Display #4 52 471 Automatic Display #5 52 472 Automatic Display #6 52 473 Automatic Display #7 52 474 Automatic Display #8 52 475 Automatic Display #9 52 476 Automatic Display #0 52 477 Variable Oscillator 53

Project # Description Page #

478 Variable Oscillator (II) 53 479

ariable Oscillator (III) 53 480 Variable Oscillator (IV) 53 481 Photo V ariable Resistor 53 482 Variable Whistle Chip Oscillator 53 483 Slow Adjusting Tone 53 484 Slow Adjusting Tone (II) 53 485 Fixed-Current Path 54 486 Simple Illumination Meter 54 487 LED V oltage Drop 55 488 Open/Closed Door Indicator 55 489 Hand-Control Meter 56 490 Light-Control Meter 56 491 Electric-Control Meter 56 492 Sound-Control Meter 56 493 Fixed-Voltage Divider 57 494 Resistor Measurement 57 495 Automatic Display Letter “b” 58 496 Automatic Display Letter “c” 58 497 Automatic Display Letter “d” 58 498 Automatic Display Letter “e” 58 499 Automatic Display Letter “h” 58 500 Automatic Display Letter “o” 58 501 Hand-Control Display 1 & 4 59 502 Hand-Control Display 1 & 0 59 503 Hand-Control Display 1 & 7 59 504 Hand-Control Display 1 & 8 59 505 Hand-Control Display 1 & 9 59 506

Monitor Capacitor Charging & Discharging

60 507 Hand-Control Space Meter 60 508 Rhythm Swinging Meter 61 509

Police Car Sound with Whistle Chip

61 510

Fire Engine Sound with Whistle Chip

61 511

Ambulance Sound with Whistle Chip

Project Listings

-8-

Project #306

OBJECTIVE: To build a one-IC AM radio.

Turn on the slide switch (S1) and adjust the variable capacitor (CV) for a radio station. Make sure you set the variable resistor (RV) control to the left for louder sound.

AM Radio

Project #307

OBJECTIVE: To build a working FM radio with adjustable volume.

Turn on the slide switch (S1) and press the R button. Now press the T button and FM module (FM) scans for a radio station. When a station is found, it locks on to it and you hear it on the speaker (SP). Adjust the volume using the adjustable resistor (RV). The resistor controls the amount of signal into the power amplifier IC (U4). Press the T button again for the next radio station. The module will scan up to 108MHz, the end of the FM band, and stop. You must then press reset (R) to start at 88MHz again.

Adjustable Volume

FM Radio

-9-

Project #308

Build the circuit shown. Turn on the slide switch (S1), you hear a beep signaling that you may begin recording. Talk into the microphone (X1) up to 5 seconds, and then turn off the slide switch (it also beeps after the 5 seconds expires).

Press the press switch (S2) for playback. It plays the recording you made followed by one of three songs. If you press the press switch before the song is over, music will stop. You may press the press switch several times to play all three songs. The lamp (L2) is used to limit current and will not light.

Playback & Record

OBJECTIVE: To demonstrate the capabilities of the recording integrated circuit.

OBJECTIVE: To play the three built-in songs on the recording IC.

Use the circuit in project #308. Turn on the slide switch (S1), then press the press switch (S2) to start the first song. When the music stops, press the press switch again to hear the second song. When the second song stops, press the press switch again, the third song plays.

Playing Music

Project #309

OBJECTIVE: To build a circuit that uses light to control the recording IC.

Light-

Controlled

Music

Project #310

OBJECTIVE: To build a circuit that lets you control the recording IC with your fingers.

Touch-

Controlled

Music

Project #311

Use the circuit in project #308. Replace the press switch (S2) with the photoresistor (RP), then turn on the slide switch (S1). Turn the music on and off by waving your hand over photoresistor.

Use the circuit in project #308. Place a single snap on base grid point F1. Replace the press switch (S2) with the PNP transistor (Q1, with the arrow on point E2) and then turn on the slide switch (S1). Turn the music on and off by touching points F1 & G2 at the same time. You may need to wet your fingers.

Visit www.snapcircuits.net or page 62 to learn about Snap Circuits®upgrade kits, which have more parts and circuits.

-10-

Project #312

Connecting the power amplifier IC (U4) to the output of the recording IC (U6), you can make much louder music than project #308.

Turn on the switch (S1), you hear a beep signaling that you may begin recording. Talk into the microphone up to 5 seconds, and then tur n open the switch (it also beeps after the 5 seconds expires).

Press the press switch (S2) for playback. It plays the recording you made followed by one of three songs. If you press switch (S2) before the song is over, music will stop. You may press the press switch several times to play all three songs.

Power Playback &

Record

OBJECTIVE: To build a circuit that amplifies the recording IC.

OBJECTIVE: To amplify the output of the recording IC.

Use the circuit in project #312. Turn on the switch (S1), then press the press switch (S2) to start the first song. When the music stops, press the press switch again to hear the second song. When the second song stops, press the press switch again, the third song plays.

Power

Amplified

Playing Music

Project #313

OBJECTIVE: Show variations of project #312.

Power Light-

Controlled

Music

Project #314

OBJECTIVE: Show variations of project #312.

Power Touch-

Controlled

Music

Project #315

Use the circuit in project #312. Replace the press switch (S2) with the photoresistor (RP), then turn on the switch (S1). Tur n the music on and off by waving your hand over photoresistor.

Use the circuit in project #312. Place a single snap on base grid point F1. Replace the press switch (S2) with the PNP transistor (Q1, with the arrow on point E2) and then turn on the slide switch (S1). Turn the music on and off by touching points F1 & G2 at the same time. You may need to wet your fingers.

-11-

Project #316

OBJECTIVE: To build a working FM radio.

The FM module (FM) contains a scan (T) and a reset (R) button. The R button resets the frequency to 88MHz. This is the beginning of the FM range. Press the T button, the module scans for the next available radio station.

Turn on the slide switch (S1) and press the R button. Now press the T button and the FM module scans for an available radio station. When a station is found, it locks on to it and y ou hear it on the speaker. Press the T button again for the next radio station. The module will scan up to 108MHz, the end of the FM band, and stop. You must then press the reset (R) button to start at 88MHz again.

FM Radio

Project #317

OBJECTIVE: To build a complex circuit.

Note that there is a 3-snap wire between RV and U4, partially hidden under R4.

This is an example of using many parts to create an unusual circuit. Set the meter (M2) to the LOW (or 10mA) scale. Turn on the slide switch (S1). As the circuit oscillates, the 7-segment display (D7) flashes the number 5 and the LED’s (D1 & D2) flash as well. The meter deflects back and forth and the speaker (SP) sounds a low tone at the same rate. The frequency of the circuit can be changed by adjusting the adjustable resistor (RV).

Next, place the 100Ω resistor (R1) directly over the diode (D3) using a 1-snap. See how this changes the circuit performance.

Mega Circuit

-12-

Project #318

OBJECTIVE: To learn the principle of an SCR.

This circuit demonstrates the principle of the SCR (Q3). The SCR can be thought of as an electronic switch with three leads: anode, cathode , and gate. Like a standard diode, it permits current flow in only one direction. It will only conduct in the forward direction when triggered by a short pulse or steady voltage applied between the gate and cathode terminals. One set of batteries powers the lamp, the other is used to trigger the SCR.

Turn on the slide switch (S1) and the bulb (L1) should not light. Now press the press switch (S2); the SCR tur ns on and lights the bulb. To turn off the bulb you must turn off the slide switch (S1).

SCR 2.5V Bulb

Project #319

OBJECTIVE: To activate a motor using an SCR.

SCR & Motor

Place the fan onto the motor (M1). In this circuit, the gate is connected to the battery (B1) through the 1KΩ resistor (R2). When the slide switch (S1) is turned on, it triggers the gate, the SCR (Q3) conducts, and the motor spins. The motor continues to spin until the switch is turned off.

WARNING: Moving parts. Do not touch the fan or

motor during operation. Do not lean o ver the motor.

To learn more about how circuits work, visit www.snapcircuits.net or page 62 to find out about our Student Guides.

-13-

Project #320

OBJECTIVE: To build a music alarm.

The alarm circuit activates when you remove the jumper wire from points A & B. The jumper wire shorts the SCR’s (Q3) gate to ground and the SCR does not conduct. Removing the jumper wire places a voltage on the gate and the SCR conducts. This connects the battery to the music IC (U1) and music is played.

Construct the circuit and you should hear no music. Now remove the jumper wire and the music starts playing.

Music Alarm

Project #321

OBJECTIVE: To build a light-music alarm.

Light-Music Alarm

Use the circuit in project #320. Replace the resistor R3 with the photoresistor (RP) and remove the jumper wire. Cover the photoresistor with your hand. Now slowly remove your hand. When enough light hits the resistor, the music plays.

Project #322

OBJECTIVE: To build a circuit that activates a bulb and motor with the amount of light present.

Cover the photoresistor (RP) with your finger. Turn on the switch (S1), and only the LED (D1) lights. The relay (S3) connects the motor (M1) and the bulb (L2) to the batteries, but the motor and bulb are powerless until a voltage is applied to the SCR's gate.

Remove your finger, as light hits the photoresistor, its resistance decreases and a voltage appears on the gate of the SCR (Q3). The SCR conducts and the motor and bulb work now.

Light-controlled SCR

WARNING: Moving parts. Do not touch the fan or

motor during operation. Do not lean o ver the motor.

-14-

Project #323

OBJECTIVE: To build a 3mA meter circuit.

3mA Meter

Project #324

OBJECTIVE: To build a voltmeter.

0-3V Voltmeter

Build this 0-3V voltmeter circuit. Set the meter (M2) to the LOW (or 10mA) setting. Using new batteries, place the battery holder between points A & B. Adjust the adjustable resistor (RV) so the meter deflects full scale.

Now you can check y our other “AA” batteries b y inserting them into the battery holder.

Set the meter (M2) to the LOW (or 10mA) scale. Inside the meter, there is a fixed magnet and a mov eable coil around it. As current flows through the coil, it creates a magnetic field. The interaction of the two magnetic fields cause the coil (connected to the pointer) to move (deflect). By itself, the meter can measure 300μA. To increase its range, resistors are connected in parallel or in series to the meter.

Build the circuit shown. Placing the 100Ω resistor (R1) in parallel with the meter increases the range by 10 times to 3mA. More current flows through the resistor than the meter. The lower the resistor value, the wider the range of the meter.

-15-

Project #325

OBJECTIVE: To understand the function of the adjustable resistor.

An adjustable resistor is a normal resistor with an additional arm contact. The arm moves along the resistive material and taps off the desired resistance.

The slider on the adjustable resistor moves the arm contact and sets the resistance between the bottom (point C1) pin and the center pin (point B2). The remaining resistance is between the center and top pin. For example, when the slider is all the way down, there is minimal resistance between the bottom and center pins (usually 0Ω) and maximum resistance between the center and top pins. The resistance between the top (point A1) and bottom (point A3) pins will always be the total resistance, (50kΩ for your part).

Set the meter (M2) to the LOW (or 10mA) scale. Adjust the adjustable resistor (RV) for maximum resistance by setting the slider to the top. The meter only deflects part of the way. As you move the slider down, decreasing the resistance, the meter deflects more.

Function of

Adjustable Resistor

Project #326

OBJECTIVE: To understand the function of the photoresistor.

Build the circuit shown. Set the meter (M2) to the LOW (or 10mA) scale. The photoresistor (RP) is a light-sensitive resistor. Its value changes from nearly infinite in total darkness to about 1,000Ω when a bright light shines on it.

The meter reading changes as the resistance changes in the circuit. When the lights are on, the meter points to a higher number on the scale. When the lights are OFF, the pointer will point to a lower number on the scale. This means that the resistance of the photoresistor is changing according to the amount of light in the room.

Function of

photoresistor

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-16-

Project #328

OBJECTIVE: To learn the principle of an SCR.

In this circuit, the 6-volt bulb (L2) will not light until the SCR (Q3) is triggered. T urn on the slide switch (S1) and the b ulb will not light. Now press the press switch (S2) to light the bulb. The bulb will stay lit until the slide switch is turned off. To protect the SCR, a current limiting 1kΩ resistor (R2) is placed in series with the gate.

SCR 6V Bulb

Project #327

OBJECTIVE: To change the direction of current flow using a motor.

Set the meter (M2) to the LOW (or 10mA) setting. A motor generates a current when it rotates. The rotation of the motor determines the direction current flows. Quickly spin the motor (M1) clockwise with your hand; the meter deflects to the right. Now spin the motor counterclockwise, and the meter deflects to the left.

Meter Deflect

by Motor

-17-

Project #329

OBJECTIVE: To demonstrate how a seven segment LED works.

The display (D7) is made up of seven segments. Each segment contains an LED connected to an input snap. When the snap is connected to the negative of the battery the segment lights. For example, connect the circuit as shown and the letter “L” lights.

Principle of

Segment LED

Project #330

OBJECTIVE: To configure the seven segment to display the number 1.

Connect B & C to the negative of the battery.

Display #1

OBJECTIVE: To configure the seven segment to display the number 2.

Connect A, B, G, E, & D to the negative of the battery.

Display #2

OBJECTIVE: To configure the seven segment to display the number 3.

Connect A, B, G, C, & D to the negativ e of the battery.

Display #3

OBJECTIVE: To configure the seven segment to display the number 4.

Connect B, C, F, & G to the negative of the battery.

Display #4

Project #331

Project #332 Project #333

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Project #334

OBJECTIVE: To configure the seven segment to display the number 5.

Connect A, F, G, C, & D to the negative of the battery.

Display #5

Project #335

OBJECTIVE: To configure the seven segment to display the number 6.

Connect A, C, D, E, F, & G to the negative of the battery.

Display #6

Project #336

OBJECTIVE: To configure the seven segment to display the number 7.

Connect A, B, & C to the negative of the battery.

Display #7

Project #337

OBJECTIVE: To configure the seven segment to display the number 8.

Connect A, B, C, D, E, F & G to the negative of the battery.

Display #8

Project #338

OBJECTIVE: To configure the seven segment to display the number 9.

Connect A, B, C, D, F, & G to the negative of the battery.

Display #9

Project #339

OBJECTIVE: To configure the seven segment to display the number 0.

Connect A, B, C, D, E, & F to the negative of the battery.

Display #0

Project #340

OBJECTIVE: See and hear the output of the music IC.

Set the meter (M2) to the LOW (or 10mA) setting. In this circuit, the output of the music IC (U1) is applied to the less windings side of the transformer (T1), which lights the LED (D1) and deflects the meter.

Place the adjustable resistor (RV) to the bottom position and turn on the switch (S1). Adjust the adjustable resistor upwards. This increases the voltage across the LED and meter. The LED brightens and the meter deflects more towards 10. Place the speaker (SP) across points A & B and use a jumper wire to complete the connection. Now you can hear and see the output of the music IC.

Music Meter

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-19-

Project #341

OBJECTIVE: Turn on and off LED’s using a relay.

A relay is an electronic switch with contacts that are opened or closed using voltage. It contains a coil that generates a magnetic field when a current flows through it. The magnetic field attracts an iron armature which switches the contacts. Contact #2 is normally closed, connecting the green LED (D2) and the resistor across the batteries.

With the slide slide switch (S1) turned off, the green LED should light. Now turn on the switch, contact #1 on the relay (S3) will switch to contact #3, lighting the red LED (D1).

LED & Relay

Project #342

OBJECTIVE: To build a manual timer using a relay.

The transistor (Q2) acts as a switch, connecting the relay (S3) to the batteries. As long as there is positive voltage on the transistor’s base, the bulb (L2) will light.

Turn on the slide switch (S1) and hold down the press switch (S2). The transistor turns on, capacitor C5 charges up, and the bulb lights. When the press switch is released, the capacitor discharges through the base, keeping the transistor on. The transistor will turn off when the capacitor is almost discharged, about 7 seconds. The relay contacts will switch and the bulb will turn off.

Change the value of the capacitor and see what happens.

Manual

7 Second Timer

-20-

Project #343

OBJECTIVE: To build a half wave rectifier circuit.

A rectifier changes an AC voltage into a DC voltage. A diode (D1) is used because it allows current to flow in only one direction, for one polarity of applied voltage. As the contacts open and close, it generates an AC voltage across the transformer (T1). We can measure the DC current from the transformer’s output using a resistor (R2), a diode (D1), and a meter (M2). Set the meter to the LOW (or 10mA) scale. Turn on the slide switch (S1), the LED lights as the meter points past the 5 scale.

Half Wave

Rectifier Circuit

OBJECTIVE: Measure the voltage using the center-tap.

Use the circuit in project #343. Now see what happens if you connect to the center-tap on the side with more windings. Place the meter (M2) across points A & B, then turn on the switch (S1). The needle should deflect less, about half as much as project #343. As you use less windings, the output decreases.

Half Wave

Rectifier

Circuit (II)

Project #344

OBJECTIVE: To see the voltage difference between an LED and diode.

Use the circuit in project #343. Replace the LED (D1) with the diode (D3) and turn on the switch (S1). The needle deflects higher, because the voltage drop across the diode is less than the voltage drop across the LED.

LED vs. Diode

Project #345

OBJECTIVE: See how resistance affects current.

Change the 1kΩ (R2) resistor to a 5.1kΩ (R3) and turn on the switch (S1). You will see that increasing the resistance decreases the current through the meter (M2).

Current &

Resistance

Project #346

-21-

Project #347

OBJECTIVE: Making telegraph sounds.

Press the press switch (S2) down. The circuit oscillates and the AC voltage generated from the transformer (T1) drives the speaker (SP). To make a telegraph sound, depress the switch for long and short periods.

Telegraph

OBJECTIVE: Show variations of project #347.

Use the circuit in project #347. Connect the whistle chip (WC) across points B & E.

Mosquito

Sound (II)

Project #349

OBJECTIVE: Show variations of project #347.

Mosquito

Sound (III)

Project #350

OBJECTIVE: To use the photoresistor to adjust the oscillator sound.

Touch-Control

Mosquito Sound

Project #351

OBJECTIVE: Use the whistle chip to make a mosquito sound.

Use the circuit in project #347. Remove the speaker (SP). Connect the whistle chip (WC) across points C & D to make a mosquito sound.

Mosquito Sound

Project #348

Use the circuit in project #347. Connect the whistle chip (WC) across points E & D (place it beneath capacitor (C2) or use the jumper wires).

Use the circuit in project #347. Replace the 100kΩ resistor (R5) with the photoresistor (RP). Wave your hand over the resistor and the sound changes.

To learn more about how circuits work, visit www.snapcircuits.net or page 62 to find out about our Student Guides.

-22-

Project #353

OBJECTIVE: To make a relay buzzer.

When you turn on the switch (S1), you should hear a buzzing sound from the relay (S3). The sound is caused by the relay’s contacts opening and closing at a fast rate.

Relay Buzzer

Project #352

OBJECTIVE: Light a bulb using a relay.

Bulb & Relay

Turn off the slide switch (S1). If you press switch (S2), the lamp (L2) will not light. T urn on the slide switch and press the press s witch again; the lamp lights and stays on until the slide switch is turned off. This circuit remembers that the press switch was pressed. Turn the slide switch off and back on again. The lamp will be off until the press switch is pressed, then the lamp will stay on. Computers use memory circuits to remember states like on and off.

Project #355

OBJECTIVE: To use a photoresistor to control a relay.

Under normal light, the resistance of the photoresistor (RP) is low, allowing a voltage at the base of the transistor (Q2). This tur ns the transistor on, connecting the relay (S3) across the batteries, and the bulb (L2) lights. If the light decreases, the resistance increases and the voltage to Q2 drops. If the voltage at Q2 decreases enough, the transistor turns off. Tur n on the slide switch (S1) and the bulb lights. Now as you block the light from the photoresistor, the bulb turns off.

Light-controlled Relay

OBJECTIVE: Make a warning system that lights the bulb.

Replace the photoresistor (RP) with a 10kΩ resistor (R4). Connect the wire to points A & B. As long as the wire is connected, the transistor (Q2) is off and the relay (S3) and bulb (L2) are not powered. Disconnect the wire. The relay contacts will switch and the bulb will light.

Bulb Alert Relay

Project #356

-23-

Project #354

OBJECTIVE: To build a manual timer using a transistor in place of the relay.

This circuit is similar to project #342 except now two transistors are used. Tur n on the slide switch (S1) and hold down the press switch (S2). The transistors (Q1 & Q2) turn on, the capacitor (C3) charges up, and the bulb (L2) lights. When the press switch (S2) is released, the capacitor discharges through the base, keeping the transistors on. The transistors will turn off when the capacitor is almost discharged (about 1 minute). The relay (S3) contacts will switch and the bulb will turn off.

Transistor Timer

-24-

Project #357

OBJECTIVE: Build an adjustable light-controlled relay.

You can set the amount of light it takes to keep the bulb (L2) on by adjusting the adjustable resistor (RV). Set the adjustable resistor to the top position and turn on the switch. The bulb lights. Cover the photoresistor (RP) and the bulb turns off. Set the adjustable resistor to different positions and then cover the photoresistor. Note that only the top half of the adjustable resistor affects the circuit. If you position it below the middle, the bulb stays off.

Adjustable Light

Control

Project #358

OBJECTIVE: To demonstrate the properties of a transformer.

Set the meter (M2) to the LOW (or 10mA) scale. Pressing the press switch (S2) generates a current on the left side of the transf ormer (T1). The current lights the LED’s (D1 & D2) and deflects the meter. There are two current paths as shown by the arrows. Placing the meter in both current paths always measures each current. The top current is produced when the press switch is pressed and the bottom current is produced when the press switch is released.

Meter Deflection

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Project #360

OBJECTIVE: To measure the current through a transformer.

Set the meter (M2) to the LOW (or 10mA) setting. By placing the meter, diode (D3) and current limiting resistor (R4) on the transfor mer (T1), you can measure the current. Turn on the slide slide switch (S1) and the motor (M1) starts spinning. The current on the right side of the transformer creates a current on the left side using magnetism.

Current Meter

-25-

Project #359

OBJECTIVE: To convert an AC current to DC using an LED.

Set the meter (M2) to the LOW (or 10mA) scale. Pressing and releasing the press switch (S2) continuously generates an AC (changing) current. The LED (D1) is used to convert the AC (changing) current to DC (unchanging) current because it only allows the current to flow in one direction. The LED should light as the meter deflects to the right only. Without the LED, the meter would deflect in both directions.

AC to DC Current

WARNING: Moving parts. Do not touch the fan or

motor during operation. Do not lean o ver the motor.

-26-

Project #361

OBJECTIVE:

To use a transformer for a louder buzzer.

Turn on the switch (S1). The speaker (SP) generates a buzzer sound. As in project #353, the relay (S3) is rapidly switched on and off. This causes an AC voltage on the left side of the transfor mer (T1). The voltage is stepped-down and applied to the speaker, generating the sound.

To make the sound a little louder, replace the 0.1μF capacitor (C2) with a 3-snap wire.

Buzzer, Relay, &

Transformer

Project #362

OBJECTIVE: Make a relay buzzer with speaker.

A speaker (SP) and capacitor (C2) are placed across the coil of the relay (S3). When the slide switch (S1) is turned on, the relay’s contacts open and close as in project #353. As the capacitor (C2) charges and discharges, the speaker generates a buzzing sound.

Buzzer & Relay

-27-

Project #363

OBJECTIVE: To configure the seven segment to display the capital letter “F”.

Connect A, E, F, & G to the negative of the battery.

Display Capital

Letter “F”

OBJECTIVE: To configure the seven segment to display the capital letter “H”.

Connect B, C, E, F, & G to the negative of the battery.

Display Capital

Letter “H”

OBJECTIVE: To configure the seven segment to display the capital letter “P”.

Connect A, B, E, F, & G to the negative of the battery.

Display Capital

Letter “P”

OBJECTIVE: To configure the seven segment to display the capital letter “S”.

Connect A, F, G, C, & D to the negative of the battery.

Display Capital

Letter “S”

Project #364

Project #365 Project #366

Project #367

OBJECTIVE: To configure the seven segment to display the capital letter “U”.

Connect B, C, D, E, & F to the negative of the battery.

Display Capital

Letter “U”

Project #370

OBJECTIVE: To configure the seven segment to display the decimal (DP).

Connect DP to the negative of the battery.

Display “.”

Project #369

OBJECTIVE: To configure the seven segment to display the capital letter “E”.

Connect A, D, E, F, & G to the negative of the battery.

Display Capital

Letter “E”

Project #368

OBJECTIVE: To configure the seven segment to display the capital letter “C”.

Connect A, D, E, & F to the negative of the battery.

Display Capital

Letter “C”

Visit www.snapcircuits.net or page 62 to learn about Snap Circuits®upgrade kits, which have more parts and circuits.

-28-

Project #376

OBJECTIVE: To hear your voice on the radio.

You need an AM radio for this project. Build the circuit sho wn and place it next to your AM radio. Tune the radio frequency to where no other station is transmitting. Push the press switch (S2); the red LED (D1) should light for a while, indicating that music is being transmitted to your radio. Tune the adjustable capacitor (CV) and the radio volume control until the music sounds best on the radio. Wait until the music stops.

Turn on the slide switch (S1), you hear a beep signaling that you may begin recording. Talk into the microphone (X1) up to 8 seconds, and then turn off the slide switch (it also beeps after the 8 seconds expires).

Recorded Voice Transmitter

Project

#371

OBJECTIVE: To configure the seven segment to display the letter “b”.

Connect C, D, E, F, & G to the negative of the battery.

Display

Letter “b”

Project

#372

OBJECTIVE: To configure the seven segment to display the letter “c”.

Connect A, F, & G to the negative of the battery.

Display

Letter “c”

Project

#373

OBJECTIVE: To configure the seven segment to display the letter “d”.

Connect B, C, D, E, & G to the negative of the battery.

Display

Letter “d”

Project

#374

OBJECTIVE: To configure the seven segment to display the letter “e”.

Connect A, B, D, E, F, & G to the negative of the battery.

Display

Letter “e”

Project

#375

OBJECTIVE: To configure the seven segment to display the letter “h”.

Connect F, E, G, & C to the negative of the battery.

Display

Letter “h”

-29-

Project #377

OBJECTIVE: To build an alarm circuit.

The circuit uses the space war IC (U3) and works the same way as project #320. Remove the jumper wire and a space war sound plays.

Space War Alarm by SCR

Project #379

OBJECTIVE: To build an alarm circuit.

Alarm by SCR

Project #378

OBJECTIVE: To build an alarm circuit.

Use the circuit in project #377. Replace the resistor (R3) with the photoresistor (RP) and remove the jumper wire. Cover the photoresistor with your hand. Now slowly remove your hand. The music plays when enough light hits the resistor.

Light Space War Alarm

The circuit uses the alarm IC (U2) and works the same way as project #377. Remove the jumper wire and an alarm IC sounds.

Project #380

OBJECTIVE: To build an alarm circuit.

Use the circuit in project #379. Replace the 10kΩ resistor (R4) with the photoresistor (RP) and remove the jumper wire. When enough light strikes the photoresistor, the Alarm IC (U2) plays. Cover the photoresistor with your hand. Now slo wly remov e it, when enough light hits the resistor, the IC plays.

Light & Alarm IC

-30-

Project #381

OBJECTIVE: To construct a time delay circuit.

Turn on the slide switch (S1) and the bulb (L2) does not light. Press switch (S2) and slowly the bulb lights.

When the press switch is pressed, current flows to the base of the transistor (Q2) and charges the 100μF capacitor (C4). When the capacitor charges up to more than 1 volt, the transistor (Q2) turns on and triggers the SCR (Q3). The bulb will stay lit until the slide switch is turned off. The values R5 and C4 determine the time it takes until the transistor turns on. The larger the capacitor value, the more time it takes to turn on.

Delay Light

Project #382 Project #383

OBJECTIVE: To construct a time delay fan.

Delay Fan

OBJECTIVE: To build a sound activated fan.

Sound Activated Fan

Use the circuit in project #381. Replace the lamp (L2) with the motor (M1) and fan, then replace the 3-snap (base grid locations E6-G6) with the lamp (L2). Turn on slide switch (S1) and press down the press s witch (S2) to start the motor.

Now replace the 100μF capacitor (C4) with the 470μF capacitor (C5). Turn on slide switch (S1) and press switch (S2). See how long it takes until the motor (M1) spins.

Build the circuit as shown. Place the fan on the motor (M1). Set the lever on the adjustable resistor (RV) toward towards the 100kΩ resistor (R5). Clap to start the motor.

WARNING: Moving parts. Do not touch the fan or

motor during operation. Do not lean o ver the motor.

To learn more about how circuits work, visit www.snapcircuits.net or page 62 to find out about our Student Guides.

WARNING: Moving parts.

Do not touch the fan or motor during operation. Do not lean over the motor.

-31-

Project #384

OBJECTIVE: To build a circuit that lights an LED to indicate the recording mode.

Recording LED

Indicator

Project #385

OBJECTIVE: To add a volt meter to the playback and record circuit.

When recording, if the input signal into the microphone (X1) is too high, distortion can occur. To monitor the level, a meter (M2) is placed in series with the microphone.

Set the meter to the LOW (or 10mA) scale. Turn on the slide switch (S1) and the meter defects to the right. As you speak into the microphone, the meter indicates the change in current. Turn the switch off and then on to record again, but this time speak louder . Y ou will find that the louder you speak, the more the meter deflects.

The lamp (L2)

is used to limit current and will not light.

Playback & Record

with Meter

The circuit uses sound (beep) and light (LED) to indicate that you are recording. Build the circuit; the red (D1) and green (D2) LED’s should light. Now turn on the slide switch (S1). You hear one beep and the green LED turns off. Speak into the microphone (X1) to record a message. When you turn off the slide switch, or the circuit beeps twice (indicating the recording is finished), the green LED turns on again. Make sure that the slide switch is turned off. Press the press switch to hear your recording followed by a song. The lamp (L2) is used to limit current and will not light.

-32-

Project #386

OBJECTIVE: To light a bulb to indicate an open circuit.

Alarm Light

Project #387 Alarm Light (II)

This is another example of a alarm that activates when the circuit is broken. Connect the jumper wire across points A & B and then tur n on the slide switch (S1). The lamp (L2) will not light until the jumper wire is disconnected. Then the lamp will not turn off. Turn off the switch to turn the lamp off again. This circuit remembers if there was a break in the connection.

OBJECTIVE: To light a bulb to indicate an open circuit.

This project is similar to project #386, but uses a transistor (Q2). The lamp (L2) will not light until the jumper wire is disconnected. The jumper wire grounds the base of the transistor , keeping it off. Remove the jumper and the voltage on the base rises; turning the transistor and SCR (Q3) on, and lighting the lamp. Note, the adjustable resistor (RV) is used as a fixed value. Once the SCR is triggered, it will light the lamp even if the jumper wire is replaced. Turn the slide switch (S1) off to turn off the lamp.

-33-

Project #388

OBJECTIVE: To build a night-sensitive police car sound.

As the photoresistor (RP) is exposed to light, its resistance is very low, thereby connecting the gate of the SCR (Q3) to ground. This prevents the SCR from conducting, connecting the alarm IC (U2) to the batteries. The alarm IC remains off until the light is blocked, triggering the SCR. If the light in the room is not bright, the IC may turn on.

Wav e y our hands ov er the photoresistor . Block the light with your hand and the speaker (SP) sounds.

Night Police Car

OBJECTIVE: To build a night-sensitive machine gun sound.

Use the circuit from project #388. Connect the jumper wire to points B & C for a machine gun sound.

Night

Machine Gun

Project #389

OBJECTIVE: To build a night-sensitive fire engine sound.

Night

Fire Engine

Project #390

OBJECTIVE: To build a night-sensitive ambulance sound.

Night

Ambulance

Project #391

Use the circuit from project #388. Connect the jumper wire to points A & B for a fire engine sound.

Use the circuit from project #388. Connect the jumper wire to points A & D for an ambulance sound.

Visit www.snapcircuits.net or page 62 to learn about more Snap Circuits®products to add to your collection.

-34-

Project #392

OBJECTIVE: To build a light-sensitive police car sound.

As long as the photoresistor (RP) is exposed to light, the alarm IC (U2) outputs a signal to the speaker (SP). Block the light with your hand and the sound will stop.

Daytime Light

Police Car

OBJECTIVE: To build a light-sensitive machine gun sound.

Use the circuit from project #392. Connect the jumper wire to points B & C. The sound of a machine gun will be heard when the room is not dark.

Daytime Light

Machine Gun

Project #393

OBJECTIVE: To build a light-sensitive fire engine sound.

Daytime Light

Fire Engine

Project #394

OBJECTIVE: To build a light-sensitive ambulance sound.

Daytime Light

Ambulance

Project #395

Use the circuit from project #392. Connect the jumper wire to points A & B for a fire engine sound, when room is not dark.

Use the circuit from project #392. Connect the jumper wire to points A & D for an ambulance sound.

-35-

Project #396 Flashing 8

OBJECTIVE: Use the Alarm IC as a switch to flash the number “8”.

Turn on the slide switch (S1) and the number 8 starts flashing. The segments are powered by connecting them to the IC’s (U2) output.

Flashing 8 with Sound

OBJECTIVE: To build a circuit so you can hear and see the 8 flash.

Use the circuit in project #396. Connect the speaker (SP) across points X & Y to see and hear the IC’s (U2) output.

Project #397

Project #398

Turn on the slide switch (S1) and you hear space war sounds as the lamp (L1) flashes. If you wave your hand over the photoresistor (RP), the sound changes. If you keep the photoresistor covered, then the sound will stop.

Press the press switch (S2) and you will hear music in addition to any space war sounds that are playing. Press the press switch again to change the music. You will also hear any recording you had made previously with other projects.

Replace the lamp with the 100Ω resistor (R1) to reduce the loudness.

Musical Space War

OBJECTIVE: To combine the sound effects of the recorder and space war integrated circuits.

-36-

Project #399

OBJECTIVE: To make different tones with an oscillator.

Build the circuit and turn on the slide switch (S1), you hear a highfrequency tone. Press the press switch (S2) and move the adjustable resistor (RV) control around to change to frequency of the tone. Replace the 0.1μF capacitor (C2) with the 10μF capacitor (C3, “+” on the right) to lower the frequency of the tone.

Electronic Noisemaker

OBJECTIVE: To show a variation of project #399.

You can also change the frequency by changing the resistance in the oscillator. Replace the 10KΩ resistor (R4) with the 100KΩ resistor (R5), this can be done with either the 0.1μF (C2) or 10μF (C3) capacitors in the circuit.

Electronic Noisemaker (II)

Project #400

Project #401

OBJECTIVE:

To make different sounds with an oscillator.

Build the circuit and press the press switch (S2) a few times, you hear cute sounds like a bumble bee. Replace the 0.02μF capacitor (C1) with 0.1μF capacitor (C2) or 10μF capacitor (C3, “+” on the right) to change the sound.

Bee

OBJECTIVE: Show a variation of project #401.

Place the 0.02μF capacitor (C1) back in the circuit. Remove the speaker (S1) from the circuit and place the whistle chip (WC) across the transformer (T1) at points labeled A & B on the circuit layout. Listen to the sounds as you press the press switch (S2). Replace the 0.02μF capacitor (C1) with 0.1μF capacitor (C2) or 10μF capacitor (C3, “+” on the right) to change the sound.

Bee (II)

Project #402

Bee (III)

Project #403

OBJECTIVE: Show a variation of project #401.

Replace the 100μF capacitor (C4) with the 10μF capacitor (C3) or the 470μF capacitor (C5) to change the duration of the sound. Use either the speaker circuit in project #401 or the whistle chip circuit in project #402.

Visit www.snapcircuits.net or page 62 to learn about Snap Circuits®upgrade kits, which have more parts and circuits.

-37-

Project #404

OBJECTIVE: Build an oscillator circuit.

Turn on the slide switch (S1) and the LED (D1) lights as the speaker (SP) emits a tone. The circuit oscillates and generates an AC voltage across the speaker through the transformer (T1).

Oscillator Sound

OBJECTIVE: Show variations of project #404.

Use the circuit in project #404. Place the whistle chip (WC) in parallel with the capacitor (C2) by placing it on the left side of the transformer (T1). T urn on the slide switch (S1) and you now hear a lower tone.

Oscillator

Sound (III)

Project #406

OBJECTIVE: Show variations of project #404.

Oscillator

Sound (IV)

Project #407

OBJECTIVE: Show variations of project #404.

Oscillator Sound (V)

Project #408

OBJECTIVE: Show variations of project #404.

Use the circuit in project #404. In this circuit, you will change the tone by adding more capacitance. Place the whistle chip (WC) on top of capacitor (C1). T urn on the slide switch (S1) and y ou now hear a lo wer tone. Adding the more capacitance lowers the oscillating frequency.

Oscillator Sound (II)

Project #405

Use the circuit in project #404. Using a 1snap, place the 10μF capacitor (C3) on top of the 100kΩ resistor (R5), with the “+” side on point A1. Turn on the slide switch (S1) and you should hear a much lower sound then the previous projects.

Use the circuit in project #404. Replace the 100kΩ resistor (R5) with the photoresistor (RP). Wave your hand over the photoresistor. Now, as the resistance changes, so does the oscillator frequency.

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Project #409

OBJECTIVE: To build a circuit that checks the transistor.

Set the meter (M2) to the LOW (or 10mA) setting. Turn on the switch (S1), the meter does not move. Press the switch (S2), the meter deflects and points to 10. This indicates the transistor (Q2) is GOOD. The meter would only deflect a little or not at all for a BAD transistor.

Transistor Tester

Project #410

OBJECTIVE: To make an adjustable current path.

Set the meter (M2) to the LOW (or 10mA) setting. This circuit is a simple voltage divider. When the adjustable resistor (RV) is set to the far right, the voltage across the resistors (R4) and (RV) are equal. Adjust resistor (RV) to the left, the meter deflects less, as the voltage decreases.

Adjustable Voltage

Divider

-39-

OBJECTIVE: To construct a flashing display for the capital letter C.

Connect segments A, D, E & F to the circuit. Tur n on the switch (S1), the display flashes and the whistle chip (WC) buzzes on and off.

Automatic Display Capital Letter “C”

Project #411

OBJECTIVE: To construct a flashing display for the capital letter E.

Use the circuit from project #411. Connect A, D, E, F, & G to the circuit. Turn on the switch (S1), the display flashes and the whistle chip (WC) buzzes on and off.

Automatic Display Capital Letter “E”

Project #412

Project #413

OBJECTIVE: To construct a flashing display for the capital letter F.

Use the circuit from project #411. Connect A, E, F, & G to the circuit. Turn on the switch (S1), the display flashes and the whistle chip (WC) buzzes on and off.

Automatic Display

Capital Letter “F”

Project #414

OBJECTIVE: To construct a flashing display for the capital letter H.

Use the circuit from project #411. Connect B, C, E , F, & G to the circuit. Turn on the switch (S1), the display flashes and the whistle chip (WC) buzzes on and off.

Automatic Display

Capital Letter “H”

Project #415

OBJECTIVE: To construct a flashing display for the capital letter P.

Use the circuit from project #411. Connect A, B, E, F, & G to the circuit. Turn on the switch (S1), the display flashes and the whistle chip (WC) buzzes on and off.

Automatic Display

Capital Letter “P”

Project #416

OBJECTIVE: To construct a flashing display for the capital letter S.

Use the circuit from project #411. Connect A, F, G, C, & D to the circuit. Tur n on the switch (S1), the display flashes and the whistle chip (WC) buzzes on and off.

Automatic Display

Capital Letter “S”

Project #417

OBJECTIVE: To construct a flashing display for the capital letter U.

Use the circuit from project #411. Connect B, C, D, E, & F to the circuit. Turn on the switch (S1), the display flashes and the whistle chip (WC) buzzes on and off.

Automatic Display

Capital Letter “U”

Project #418

OBJECTIVE: To construct a flashing display for the capital letter L.

Use the circuit from project #411. Connect D, E, & F to the circuit. Turn on the switch (S1), the display flashes and the whistle chip (WC) buzzes on and off.

Automatic Display

Capital Letter “L”

To learn more about how circuits work, visit www.snapcircuits.net or page 62 to find out about our Student Guides.

-40-

OBJECTIVE: Show variations of project #419.

Connect the whistle chip (WC) across points B & C.

Whistle Chip Sounds (II)

Project #420

OBJECTIVE: Show variations of project #419.

Whistle Chip

Sounds (III)

Project #421

OBJECTIVE: Show variations of project #419.

Whistle Chip Sounds (VI)

Project #424

OBJECTIVE: To make sounds from the whistle chip.

Turn on the switch (S1). As the circuit oscillates, the plate in the whistle chip vibrates and generates sound.

Whistle Chip Sounds

Project #419

Use the circuit in project #419. Connect the whistle chip (WC) across points C & D. You should hear a faster sound.

OBJECTIVE: Show variations of project #419.

Whistle Chip

Sounds (V)

Project #423

Use the circuit in project #419

, but replace the 100μF capacitor (C4) with

the 470μF capacitor (C5).

Use the circuit in project #419, but replace the 100μF capacitor (C4) with the 10μF capacitor (C3).

OBJECTIVE: Show variations of project #419.

Whistle Chip Sounds (IV)

Project #422

Use the circuit in project #419, but replace the 100μF capacitor (C4) with the 10μF capacitor (C3) and connect the whistle chip across points B & C. You can also connect the whistle chip across points C & D.

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Project #425

OBJECTIVE: To light the LED’s using the recording IC.

The recording IC (U6) lights the LED’s (D1 & D2) instead of driving the speaker (SP). Press the press switch (S2) once. The LED’s light and then turn off after a while. Press the press switch again and see how long the second song plays. When the second song stops, press the press switch (S2) again to play the third song.

LED Music

Project #426 Project #427

OBJECTIVE: Show variations of project #425.

Light-controlled LED

Time Delay

OBJECTIVE: Show variations of project #425.

Touch-controlled LED

Time Delay

Use the circuit in project #425. Replace the press switch (S2) with the photoresistor (RP). Tur n the LED’s on and off by waving your hand over the photoresistor.

Use the circuit in project #425. Replace the press switch (S2) with the PNP transistor (Q1, arrow on U6 and a 1-snap on point F1). Turn the LED’s on and off by touching grid points F1 & G2 at the same time. You may need to wet your fingers.

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Project #428

OBJECTIVE: To record the sound from the alarm IC.

The circuit records the sound from the alarm IC (U2) into the recording IC (U6). Tur n on the switch (S1). The first beep indicates that the IC has begun recording. When you hear two beeps, the recording has stopped. Turn off the slide switch (S1) and press the switch (S2). You will hear the recording of the alarm IC before each song is played. The lamp (L2) is used to limit current and will not light.

Alarm Recorder

Project #429 Project #430

OBJECTIVE: Record the sound from the alarm IC.

Alarm Recorder (II)

OBJECTIVE: To record the sound of a machine gun.

Machine Gun Recorder

Use the circuit in project #428. Remove the 2-snap from A1 to B1. Turn on the switch (S1). The first beep indicates that the IC (U6) has begun recording. When you hear two beeps, turn off the switch (S1), press the switch (S2), and the new recording plays.

Use the circuit in project #428. Move the 2-snap from A1 - B1 to 3A 3B. Turn on the switch (S1). The first beep indicates that the IC (U6) has begun recording. When you hear two beeps, turn off the switch (S1), press the switch (S2), and the machine gun sound plays.

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The length of time the motor (M1) runs depends on the position of the adjustable resistor (RV). When the press switch (S2) is pressed, the 470μF capacitor (C5) charges. As the press switch is released, C5 discharges through the resistors R4 and RV, turning the transistor (Q2) on. Transistor Q2 connects the relay (S3) to the batteries, the contacts switch, and the motor (M1) spins. As the voltage decreases, Q2 will turn off and the motor will stop spinning.

Setting RV to the right (large resistance) sets a long discharge time. To the left, a short discharge time.

Turn on the switch (S1), the red LED (D1) lights. Now press and release the switch (S2), the bulb lights and the motor spins.

Project #431

Time Delay

1-7 Seconds

OBJECTIVE: To build a time delay circuit.

Project #432

Time Delay

OBJECTIVE: To see how the capacitor value affects the time.

Use the circuit in project #431. Replace the 470μF capacitor (C5) with the 100μF capacitor (C4). Set the adjustab le resistor (RV) to the far right, turn on the switch (S1), then press and release the switch (S2). The motor (M1) spins and bulb (L2) lights for about 3 seconds. Adjust the adjustable resistor to the left for a much shorter time.

WARNING: Moving parts. Do not touch the fan or

motor during operation. Do not lean o ver the motor.

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Project #433

OBJECTIVE: To build a manual timer using a relay and whistle chip.

This circuit is similar to project #431 except now the whistle chip (WC) will also make sound.

Manual 7 Second

Timer (II)

Project #434

OBJECTIVE: To build a circuit that sounds the speaker for 15 seconds.

As in project #431, the transistor (Q2) acts as a switch, connecting the relay (S3) and the alarm IC (U2) to the batteries. As long as there is a voltage on the transistor's base, the alarm IC sounds.

Turn on the slide switch (S1) and then press the switch (S2). The transistor turns on, the capacitor (C5) charges up, and the alarm sounds. Release the press switch (S2). As the capacitor discharges, it keeps the transistor on. The transistor will turn off when the capacitor is almost discharged, about 15 seconds. The relay contacts will switch and the alarm will turn off.

15 Second Alarm

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Project #441 Project #442

OBJECTIVE: Use the Alarm IC as a switch to flash the numbers “1 & 2”.

Connect segments B & C to the circuit. Turn on the slide switch (S1) and the number “1” should be flashing. Now, connect A, B, G, E, & D to flash the number “2”.

OBJECTIVE: Use the Alarm IC as a switch to flash the letters “d & e”.

Flashing “d & e”

Use the circuit in project #435.

Connect B, C, D, E,

& G to the circuit.

Turn on the slide switch (S1) and the letter “d” should be flashing. Now, connect A, B, D, E, F & G to flash the letter “e”.

OBJECTIVE: Use the Alarm IC as a switch to flash the letters “h & o”.

Flashing “h & o”

Use the circuit in project #435.

Connect C, E, F, &

G to the circuit.

Turn on the slide switch (S1) and the letter “h” should be flashing. Now, connect C, D, E, & G to flash the letter “o”.

Project #436

OBJECTIVE: Use the Alarm IC as a switch to flash the numbers “3 & 4”.

Flashing “3 & 4”

Use the circuit in project #435. Connect A, B, G, C, & D to the circuit. Turn on the slide switch (S1) and the number “3” should be flashing. Now, connect C, B, G & F to flash the number “4”.

Project #437

OBJECTIVE: Use the Alarm IC as a switch to flash the numbers “5 & 6”.

Flashing “5 & 6”

Use the circuit in project #435. Connect A, F, G, C & D to the circuit. Turn on the slide switch (S1) and the number “5” should be flashing. Now, connect A, C, D , E, F & G to flash the number “6”.

Project #438 Project #439 Project #440

OBJECTIVE: Use the Alarm IC as a switch to flash the numbers “7 & 8”.

Flashing “7 & 8”

Use the circuit in project #435. Connect A, B, & C to the circuit. Turn on the slide switch (S1) and the number “7” should be flashing. Now, connect A, B, C, D, E, F & G to flash the number “8”.

OBJECTIVE: Use the Alarm IC as a switch to flash the numbers “9 & 0”.

Flashing “9 & 0”

Use the circuit in project #435. Connect A, B, C, D, F, & G to the circuit. Turn on the switch (S1) and the number “9” should be flashing. Now, connect A, B, C, D, E, & F to flash the number “0”.

OBJECTIVE: Use the Alarm IC as a switch to flash the letters “b & c”.

Flashing “b & c”

Use the circuit in project #435.

Connect C, D, E, F

& G to the circuit.

Turn on the slide switch (S1) and the letter “b” should be flashing. Now, connect A, F & G to flash the letter “c”.

Project #443

OBJECTIVE: Use the Alarm IC as a switch to flash the letters “A & J”.

Flashing “A & J”

Use the circuit in project #435. Connect A, B, C, E, F, & G to the circuit. Turn on the slide switch (S1) and the capital letter “A” should be flashing. Now, connect B, C, & D to flash the capital letter “J”.

Flashing “1 & 2”

Project #435

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Project #445

Alarm Timer (II)

OBJECTIVE: To change the time by switching the resistor and capacitor.

Project #446

Alarm Timer (III)

Build this circuit using the following combinations for R5 and C5:

R5 & C3, R4 & C4, and R4 & C5.

OBJECTIVE: To modify project #285 for a different sound.

Project #444

OBJECTIVE: To connect the alarm IC to a timer circuit.

Alarm Timer

Turn on the slide switch (S1) and the alarm may sound and slowly drift away as the lamp (L2) brightens. Press the press switch (S2) and the alarm sounds at full volume as the LED (D1) lights. Capacitor C5 is also charged. Release the press switch; the alarm IC (U2) still sounds because the voltage from the discharging C5 keeps Q1 and Q2 off . As the capacitor’s voltage drops, the LED will turn off and the sound will slowly stop.

Replace resistor R5 and capacitor C5 with different values and see how it affects the circuit.

Replace the 1-snap wire from the middle snap on U2 with a 2snap and connect it to grid location D7 & E7. The circuit now produces a different sound. Change R5 and C5 with the following combinations for R5 and C5:

R5 & C3, R4 & C4, and R4 & C5.

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OBJECTIVE: To create bird sounds.

Turn on the switch (S1). The circuit makes a bird sound.

Bird Sounds

Project #447

OBJECTIVE: To create bird sounds.

Use the circuit in project #447. Replace the 100μF (C4) capacitor with the 10μF capacitor (C3), the tone should sound like a buzzer. Now use the 470μF capacitor (C5) and hear how the tone gets longer between chirps.

Bird Sounds (II)

Project #448

OBJECTIVE: To create bird sounds.

Use the circuit in project #447. Using the jumper wires, connect the whistle chip (WC) across points A & B and the sound changes.

Bird Sounds (III)

Project #449

OBJECTIVE: To create bird sounds.

Use the circuit in project #447. Connect the whistle chip (WC) across points B & C.

Bird Sounds (IV)

Project #450

OBJECTIVE: To create bird sounds.

Use the circuit in project #447. Replace the 100kΩ resistor (R5) with the photoresistor (RP). Wave your hand over the resistor and the sound changes. With the photoresistor installed, redo projects #448 - 451.

Bird Sounds (V)

Project #451

OBJECTIVE: Show variations of project #447.

Using the jumper wires, connect the whistle chip (WC) across points C & D.

Touch-Control

Bird Sound

Project #452

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Project #453

OBJECTIVE: Build a circuit that records the sound of the motor spinning.

Placing the motor (M1) (with the fan attached) next to the microphone (X1) enables you to record the sound as it spins. Turn off and then turn on the switch (S1). After the two beeps, turn off the slide switch (S1) again. Remove the jumper wire connected across points A & B and press the press switch (S2) to hear the recording. The lamp (L2) is used to limit the current and will not light.

Motor Sound

Recording

Project #454

OBJECTIVE: To build a circuit that generates sound as a motor is spinning.

Turn off the switch (S1). There is no power; the LED’s and motor are off. Now turn on the switch (S1). Only the green LED (D2) lights, indicating power to the circuit. Press the s witch (S2). The motor spins, the red LED (D1) lights, and you hear the motor sound from the speaker (SP).

Motor Sound Indicator

WARNING: Moving parts. Do not touch the fan or

motor during operation. Do not lean o ver the motor.

WARNING: Moving parts. Do not touch the fan or

motor during operation. Do not lean o ver the motor.

To learn more about how circuits work, visit www.snapcircuits.net or page 62 to find out about our Student Guides.

-49-

Project #455

OBJECTIVE: Use the whistle chip and relay to make sound.

Turn on the slide switch (S1) and the relay (S3) opens and closes continuously. This creates an AC voltage across the whistle chip (WC), causing it to vibrate and sound.

Relay & Buzzer

Project #456

Project #457

OBJECTIVE: Use the speaker and relay to make sound.

Relay & Speaker

OBJECTIVE: To see how much fun electronics can be.

Electronic Playground

Use the circuit from project #455. Replace the whistle chip (WC) with the speaker (SP). Turn on the slide switch (S1) and now you generate a louder sound using the speaker.

Next, replace the whistle chip (WC) with the 6V lamp (L2). Turn on the slide switch (S1) and the lamp lights.

Uncover the photoresistor (RP) to play a recorded message followed by music, cover it to stop the music.

Turn on the slide switch (S1), you hear a beep signaling that you may begin recording. Talk into the microphone (X1) up to 5 seconds, and then turn off the slide switch (it also beeps after the 5 seconds expires).

Set the lever on the adjustable resistor (RV) down (towards the microphone). Push and release the press switch (S2); the green LED (D2) flashes once while the red LED (D1) stays on longer. The LEDs will be brighter if your batteries are new.

-50-

OBJECTIVE: To create the sound of a cat.

Set the adjustable resistor (R V) to the f ar left. Press and release the switch (S2). You should hear the sound of a cat from the speaker (SP). Now adjust the resistor and hear the different sounds.

Electronic Cat

Project #458

OBJECTIVE: Show variations of project #458.

Electronic Cat (II)

Project #459

Use the circuit in project #458. Connect the whistle chip (WC) across points A & B. Press and release the the switch (S2). You hear sound from the whistle chip and speaker (SP). Adjust the resistor (RV) and hear the different sounds.

Project #460

OBJECTIVE: Show variations of project #458.

Electronic Cat (III)

Project #461 Project #462

Project #463 Project #464 Project #465

Use the circuit in project #458. Using the jumper wires, connect the whistle chip (WC) across points B & C. Press and release the switch (S2). Adjust the resistor (RV) and hear the different sounds.

OBJECTIVE: Show variations of project #458.

Electronic Cat (IV)

Use the circuit in project #458. Connect the whistle chip (WC) across points C & D. Press and release the switch (S2). Adjust the resistor (RV) and hear the different sounds.

OBJECTIVE: Show variations of project #458.

Buzzer Cat

Use the circuit in project #458. Remove the speaker (SP) and connect the whistle chip (WC) across points A & B. Press and release the press switch (S2) to hear the sounds.

OBJECTIVE: Show variations of project #458.

Buzzer Cat (II)

Use the circuit in project

#458

. Remove the speaker (SP) and, using the jumper wires, connect the whistle chip (WC) across points B & C. Press and release the switch (S2). Adjust the resistor (RV) and hear the different sounds.

OBJECTIVE: Show variations of project #458.

Buzzer Cat (III)

Use the circuit in project #458. Remove the speaker (SP) and connect the whistle chip (WC) across points C & D. Press and release the switch (S2). Adjust the resistor (RV) and hear the different sounds.

OBJECTIVE: Show variations of project #458.

Lazy Cat

Use the circuit in project #458. Replace the 100μF capacitor (C4) with 470μF (C5). Repeat projects #459-464 and hear 7 different sounds.

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OBJECTIVE: Construct a light-controlled display.

Connect segments B & C to the circuit. Tur n on the switch (S1), the display should be off. Place your hand over the photoresistor (RP), now the number 1 lights.

Automatic Display #1

Project #467

OBJECTIVE: Light the number 2 using a light-controlled display.

Use the circuit from project #467. Connect A, B, G, E, & D to the circuit. Tur n on the switch (S1), the display should be off. Place your hand over the photoresistor (RP), now the number 2 lights.

Automatic Display #2

Project #468

Project #466

OBJECTIVE: To build change the direction in which current flows.

Compare this circuit to project #358, which has the LED (D1 & D2) positions reversed. This changes the direction that current can flow. Set the meter (M2) to the LOW (or 10mA) scale. Press the press switch (S2) and now the meter deflects to the left.

Meter Deflection (II)

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-52-

Project #469

OBJECTIVE: Light the number 3 using a light-controlled display.

Use the circuit from project #467. Connect A, B , G, C, & D to the circuit. Tur n on the switch (S1), the display should be off. Place your hand over the photoresistor (RP), now the number 3 lights.

Automatic Display #3

Project #475

OBJECTIVE: Light the number 9 using a light-controlled display.

Use the circuit from project #467. Connect A, B, D, F, G, & C to the circuit. Turn on the switch (S1), the display should be off. Place your hand over the photoresistor (RP), now the number 9 lights.

Automatic Display #9

Project #476

OBJECTIVE: Light the number 0 using a light-controlled display.

Use the circuit from project #467. Connect A, B, C, D, E & F to the circuit. Tur n on the switch (S1), the display should be off. Place your hand over the photoresistor (RP), now the number 0 lights.

Automatic Display #0

Project #470

OBJECTIVE: Light the number 4 using a light-controlled display.

Use the circuit from project #467. Connect B , G, C, & F to the circuit. Turn on the switch (S1), the display should be off. Place your hand over the photoresistor (RP), now the number 4 lights.

Automatic Display #4

Project #471

OBJECTIVE: Light the number 5 using a light-controlled display.

Use the circuit from project #467. Connect A, C, F, G, & D to the circuit. Turn on the switch (S1), the display should be off. Place your hand over the photoresistor (RP), now the number 5 lights.

Automatic Display #5

Project #472

OBJECTIVE: Light the number 6 using a light-controlled display.

Use the circuit from project #467. Connect A, C, D, E, F, & G to the circuit. Turn on the switch (S1), the display should be off. Place your hand over the photoresistor (RP), now the number 6 lights.

Automatic Display #6

Project #473

OBJECTIVE: Light the number 7 using a light-controlled display.

Use the circuit from project #467. Connect A, B, & C to the circuit. Turn on the s witch (S1), the display should be off. Place your hand over the photoresistor (RP), now the number 7 lights.

Automatic Display #7

Project #474

OBJECTIVE: Light the number 8 using a light-controlled display.

Use the circuit from project #467. Connect A, B, C, D, E, F & G to the circuit. Turn on the switch (S1), the display should be off. Place your hand over the photoresistor (RP), now the number 8 lights.

Automatic Display #8

-53-

OBJECTIVE: To change the tone using the adjustable resistor.

Set the adjustable resistor (R V) to the bottom position. Turn on the slide switch (S1) and you should hear sound from the speaker (SP). Adjust the resistor to hear the different sounds.

Variable Oscillator

Project #477

OBJECTIVE: To change the tone using the adjustable resistor.

Variable Oscillator (II)

Project #478

Project #479

Use the circuit in project #477. Connect the whistle chip (WC) across points B & C and adjust the resistor (RV).

Variable Oscillator (III)

Project #480

OBJECTIVE: Show variations of project #477.

Variable Oscillator (IV)

Project #481

OBJECTIVE: Show variations of project #477.

Photo Variable Resistor

Use the circuit in project #477. Connect the whistle chip (WC) across points A & B and adjust the resistor (RV). You should hear a higher tone. This is generated by the whistle chip (WC).

Project #482

OBJECTIVE: Show variations of project #477.

Variable Whistle

Chip Oscillator

Project #483

OBJECTIVE: Show variations of project #477.

Slow Adjusting

Tone

Project #484

OBJECTIVE: Show a variation of project #483.

Slow Adjusting

Tone (II)

Use the circuit in project #477. Connect the whistle chip (WC) across points D & E and adjust the resistor (RV).

Use the circuit in project #477.

Replace the 100kΩ resistor (R5) with the photoresistor (RP). Wave your hand over the resistor and the sound changes. Adjust the resistor (RV) to make more sounds.

Use the circuit in project #477, remove the speaker (SP). Make three more sounds by placing the whistle chip (WC) across points, A & B, B & C, and D & E.

Use the circuit in project #477. Place the 10μF capacitor (C3) (+ towards the top) directly over the .02μF capacitor (C1). A tone is generated once or twice per second, depending on the resistor setting.

Use the circuit in project #483. Replace the 10μF capacitor (C3) with the 100μF capacitor (C4) and the tone is much slower . To mak e it e ven slo wer, replace the 100μF capacitor (C4) with the 470μF capacitor (C5).

OBJECTIVE: Show variations of project #477.

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Project #485

OBJECTIVE: To make a fixed-current path.

Set the meter (M2) to the LOW (or 10mA) setting.

The meter indicates the amount of current in the circuit. Tur n on the switch (S1), the needle deflects indicating the amount of current. The 10kΩ resistor limits the current, otherwise the meter could be damaged.

Fixed-Current Path

Project #486

OBJECTIVE: To make a simple light meter.

Set the meter (M2) to the LOW (or 10mA) setting. Using only a few parts, you can make a simple light meter. The amount of light changes the resistance of the photoresistor (RP), which affects the current though the meter. As light increases, the resistance drops and the meter deflects to the right. Decreasing the light, the meter deflects to the left, indicating less current.

Set the adjustable resistor (RV) to the far left and turn on the slide switch (S1). The circuit is now very sensitive to light. Wave your hand over the photoresistor (RP) and the meter deflects to the left, almost to zero. Move the adjustable resistor to the far right and see how less sensitive the circuit is to light now.

Simple Illumination

Meter

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-55-

Project #487

OBJECTIVE: To measure the voltage drop across diodes.

Set the meter (M2) to the LOW (or 10mA) setting.

Turn on the slide switch (S1) and the LED (D1) lights as the meter deflects to the middle of the scale. The sum of the voltage drop across each components equals the battery voltage. Bypass the LED by pressing the switch (S2). The voltage across the 10kΩ resistor increases, as shown by the meter deflecting more to the right. Replace the red LED with the green LED (D2) and then the diode (D3), to see the different voltage drops.

LED Voltage Drop

Project #488

OBJECTIVE: To make a circuit that indicates whether a door is open or closed.

Using the photoresistor (RP) you can build a circuit that indicates if a door is open or closed. When the door is open and light is present, the letter “O” lights. When the door is closed and the room is dark, the letter C lights.

The photoresistor turns the transistor (Q2) on or off, depending on the amount of light in the room. When the transistor is on (light present), segments B & C connect to the (–) side of the batteries and letter “O” lights. When the room is dark, the transistor is off and the letter “C” lights . Segments B & C are connected to the transistor.

Turn the slide switch (S1) on and the letter “O” should light. Cover the photoresistor, simulating closing the door, and the letter “C” lights.

Open/Closed Door

Indicator

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Project #489

Set the meter (M2) to the LOW (or 10mA) setting. Instead of driving a speaker (SP) with the music IC (U1), you can see it b y using the meter . Turn on the slide switch (S1) and the meter deflects according to the rhythm of music. After the music stops, hold down the press switch (S2) to make it continue.

Hand-control Meter

OBJECTIVE: To understand music deflection.

OBJECTIVE: To control the circuit using light.

Use the circuit in project #489. Replace the press switch (S2) with the photoresistor (RP). The music IC (U1) outputs a signal, as long as a light is present on the photoresistor. The photoresistor is like a short, connecting the pin to the battery. When the song repeats, cover the photoresistor with your hand, the resistance goes up, and the music stops.

Light-control

Meter

Project #490

OBJECTIVE: To start the circuit using an electric motor.

Electric-

control Meter

Project #491

OBJECTIVE: To start the circuit by using the whistle chip.

Sound-control

Meter

Project #492

Use the circuit in project #489. Place the motor (M1) across points A & B. Turn on the slide switch (S1) and the meter (M2) deflects and swings according to the rhythm of music. When deflection stops, rotate motor to start the music again. The voltage generated by the motor triggers the IC again.

Use the circuit in project #489. Place the whistle chip (WC) across points A & B. Turn on the slide switch (S1) and the meter (M2) deflects and swings according to the rhythm of music. When deflection stops, clap your hands next to the whistle chip, the m usic pla ys again. The clapping sound vibrates the plates in the whistle chip, creating the voltage needed to trigger the IC.

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Project #493

OBJECTIVE: To make a simple voltage divider.

Set the meter (M2) to the LOW (or 10mA) scale.

This circuit is a simple voltage divider with parallel load resistors. The voltage across resistors R3 & R4 is the same. The current through both paths are different, due to the resistor values. Since resistor (R3) (5.1kΩ) is half the value of resistor (R4) (10kΩ), twice the current flows through R3.

The lights in a house are an example of this type of circuit. All are connected to the same voltage, but the current is dependent on the wattage of the bulb.

Fixed-Voltage Divider

Project #494

OBJECTIVE: To make a resistor checker.

Set the meter (M2) to the LOW (or 10mA) setting.

Connect the jumper wire to points A & B. Adjust the adjustable resistor (RV) so the meter deflects to 10. The resistance between points A & B is zero. Remove the jumper wire and put the 100Ω resistor (R1) across points A & B. The meter deflects to the 10, indicating a low resistance. Now replace resistor (R1) with the other resistors. The meter will display different readings for each resistor.

Resistor Measurement

To learn more about how circuits work, visit www.snapcircuits.net or page 62 to find out about our Student Guides.

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OBJECTIVE: To construct a light-controlled display for lower case letters.

Connect C, D, E, F & G to the circuit. Turn on the slide switch (S1) and the display should be off. Place your hand over the photoresistor (RP), now the letter “b” lights.

Automatic Display Letter “b”

Project #495

Project #497

OBJECTIVE: To light the letter “d” using a light-controlled display.

Use the circuit from project #495. Connect B, C, D, E, & G to the circuit. Turn on the slide switch (S1) and the display should be off. Place your hand over the photoresistor (RP), now the letter “d” lights.

Automatic Display Letter “d”

OBJECTIVE: To light the letter “c” using a light-controlled display.

Use the circuit from project #495. Connect E, D, & G to the circuit. Turn on the slide switch (S1) and the display should be off. Place your hand over the photoresistor (RP), now the letter “c” lights.

Automatic Display Letter “c”

Project #496

Project #498

OBJECTIVE: To light the letter “e” using a light-controlled display.

Use the circuit from project #495. Connect A, B, D, E, F, & G to the circuit. Turn on the slide switch (S1) and the display should be off. Place your hand over the photoresistor (RP), now the letter “e” lights.

Automatic Display Letter “e”

Project #499

OBJECTIVE: To light the letter “h” using a light-controlled display.

Use the circuit from project #495. Connect F, E, C, & G to the circuit. Turn on the slide switch (S1) the display should be off. Place your hand over the photoresistor (RP), now the letter “h” lights.

Automatic Display Letter “h”

Project #500

OBJECTIVE: To light the letter “o” using a light controlled display.

Use the circuit from project #495. Connect C, D, E, and G to the circuit. Turn on the slide switch (S1) the display should be off. Place your hand over the photoresistor (RP), now the letter “o” lights.

Automatic Display Letter “o”

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Project #501

OBJECTIVE: Display numbers 1 or 4 using the slide switch.

Connect segments B, C, F, & G as shown in the diagram. Turn the slide switch (S1) off and on, the display changes from numbers 1 to 4.

Hand-Control Display 1 & 4

Project #502

OBJECTIVE: Display numbers 1 or 0 using the slide switch.

Connect segments A, B, C, D, E, & F as shown in the diagram. Tur n the slide switch (S1) off and on, the display changes from numbers 1 to 0.

Hand-Control Display 1 & 0

Project #503

OBJECTIVE: Display numbers 1 or 7 using the slide switch.

Connect segments A, B, & C as shown in the diagram. T urn the slide s witch (S1) off and on, the display changes from numbers 1 to 7.

Hand-Control

Display 1 & 7

Project #504

OBJECTIVE: Display numbers 1 or 8 using the slide switch.

Connect segments A, B, C, D, E, F, & G as shown in the diagram. Turn the slide switch (S1) off and on, the display changes from numbers 1 to 8.

Hand-Control

Display 1 & 8

Project #505

OBJECTIVE: Display numbers 1 or 9 using the slide switch.

Connect segments A, B, C, D, F, & G as shown in the diagram. Turn the slide switch (S1) off and on, the display changes from numbers 1 to 9.

Hand-Control

Display 1 & 9

Project #506

OBJECTIVE: View charging and discharging a capacitor.

Using the meter (M2), we can monitor the charging and discharging of a capacitor. First turn off the switch (S1).

Charging: Connect the meter (M2) to points A & B (positive pole downward). Turn on the switch (S1). The 100μF capacitor (C4) charges and the meter deflects, slowly returning to zero.

Discharging: Connect the meter to points B & C (positive pole downward). Press the switch (S2). The capacitor discharges and the meter deflects, slowly returning to zero.

Monitor Capacitor

Charging &

Discharging

Project #507

OBJECTIVE: Using the meter with the space war IC.

Set the meter (M2) to the LOW (or 10mA) setting.

This is another circuit using the meter to monitor the output of an IC. Turn on the switch (S1). Press switch (S2) to start the circuit. As the space war IC (U3) outputs a signal, the meter will deflect. When the circuit stops, start it again by pressing switch (S2).

Hand-Control

Space Meter

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Project #508

OBJECTIVE: Use the meter with the alarm IC.

Set the meter (M2) to the LOW (or 10mA) setting. Connect 3-snap wires to terminals E & F, and C & D. Turn on the slide switch (S1) and the meter swings rhythmically.

Rhythm Swinging

Meter

OBJECTIVE: Show variations of project #508.

Fire Engine

Sound with

Whistle Chip

Project #510

OBJECTIVE: Show variations of project #508.

Ambulance Sound with

Whistle Chip

Project #511

Connect 3-wire snaps to terminals C & D and A & B. Connect the whistle chip (WC) across points G & H. You should hear a fire engine sound generated by the alarm IC (U2).

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Connect a 3-wire snap to terminals C & D. Connect the whistle chip (WC) across points G & H. Connect a jumper wire to terminals B & H. You should hear an ambulance sound generated by the alarm IC (U2).

OBJECTIVE: Show variations of project #508.

Police Car

Sound with

Whistle Chip

Project #509

Use the circuit in project #508. Connect the whistle chip (WC) to points G & H. Connect a 3-wire snap to the terminals C & D and turn on the switch (S1).

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OTHER SNAP CIRCUITS®PRODUCTS!

For a listing of local toy retailers who carry Snap Circuits®, please visit www.elenco.com or call us toll-free at (800) 533-2441. For Snap Circuits®upgrade kits, accessories, additional parts, and more information about your parts, please visit www.snapcircuits.net.

OTHER FUN ELENCO®PRODUCTS

Motion Detector

Model SCP-03

Whenever somebody walks in front of the Motion Detector, the sound of a laser comes out of the speaker!

Snaptricity

Model SCBE-75

Build Over 75 Projects

Learn how electricity and magnetism can be used to make each other, learn about magnetic fields, how the electricity in your home works, how switches control the electricity to the lights in your home, and how series and parallel circuits affect electricity.

Over 40 parts including: Meter, electromagnet, motor, lamps, switches, fan, compass, and electrodes.

Educational Toy: Projects that relate to electricity in the home and magnetism and how it is used. Build over 75 projects.

RC Car Kit

Model FUN-875

Your Turbo King Car will be built from the ground up. You’ll learn all about gears, motors, printed circuit boards, and integrated circuits from our detailed assembly and training manual. You will construct each section, explore the circuitry and troubleshoot it.

300-in-1 Project Lab

Model MX-908

This lab has everything you need to build 300 exciting electronic projects. It uses spring and breadboard hook-up methods and includes an easy-to-read, illustrated, lab-style manual. Projects include: Transistor Radio, Burglar Alarm, Metal Detector, and much more!

Titan T ank Kit

Model 21-531N

The Titan Tank is an infrared remote control kit. Its microprocessor provides four different channels that allow up to four Titans to fight each other at the same time. Makes a sound when shooting and when it is hit. The Titan moves using six wheels that can move

forward, backward,

right and

left.

Upgrade Kit

Model UC-80

Deluxe Snap Rover

Model SCROV-50

Introducing the next generation of the RC Snap Rover®! This version includes a disc launcher , digital voice recorder, and music sounds. Over 50 parts allow you to complete over 40 additional projects.

If you want to enhance your Snap Circuits

experience and get even smarter, then try

For use with SC-500

Educational Series - teaches Basic Electricity and Electronics in the everyday world using our Learn By Doing®concept! 80 full-color pages, and written with the help of educators.

Put your circuits

in motion!

• Includes 30 parts

• Build over 20 projects

• Full-color assembly manual

• Sound effects

Build 250 Additional Projects

Including:

• Strobe light

• Electromagnetism

• Transistor AM radio

• Rechargeable battery

• Solar batteries

• Mega pulser and flasher

• Paperclip compass

Contains 10 New Parts

Including:

• Solar cell

• Electromagnet

• Vibration switch

• Two-spring socket

• Bag of paperclips

• Plus all experiments contained in the 500-in-1 (SC-500)!

• Includes CI-73 Computer Interface!

With this module you will also learn about and use an oscilloscope and spectrum analyzer, as you build over

73 BONUS EXPERIMENTS

using your Windows-based PC. Comes with all of the interface parts you need and the software. Great for introducing electronics through a computer. Works with all versions of our Snap Circuits

Sample Screen of

Computer Experiment

Expansion Parts

AC Power Supply

Part #

AC-SNAP

Replaces the batteries in Snap Circuits

Snap-to-Pin Set

Part # 9JWSC10

Lets you connect Snap Circuits®to a breadboard. 10 wires with reinforced pins, 5 colors, 10” length, and unlimited possibilies!

Computer Interface for

Snap Circuits

Model CI-73

Two-spring Socket

Part # ? 1

Three-spring Socket

Part # ? Q

Eight-Pin IC Socket

Part # ? U 8

Acts as a Scope and Allows You to See the Signals in the Circuit.

Snap Circuits®Green

Alternative Energy Kit

Model SCG-125

Learn about energy sources and how to “think green”. Build ov er 125 projects and ha ve loads of fun learning about environmentally-friendly energy and how the electricity in your home works. Includes full-color manual with over 100 pages and separate educational manual. This educational manual will explain all the forms of environmentally-friendly energy including: geothermal, hydrogen fuel cells, wind, solar, tidal, hydro, and others. Contains over 40 parts.

Snap Circuits®LIGHT

Model SCL-175

• Infrared detector

• Strobe light

• Color changing LED

• Glow-in-the-dark fan

• Strobe integrated circuit (IC)

• Fiber optic communication

• Color organ controlled by iPod

or other MP3 player, voice, and fingers.

Build over 175

projects!

Contains over

60 parts

Features:

Custom Storage Case

Model SNAPCASE7

Heavy duty plastic case with 2 custom foam inserts for housing your Snap Circuits®parts. Easy to identify missing components. Also includes a separate small case to hold the smaller loose parts.

(for use with SC-500)

Snap Circuits® Student Guide

Part # 753307

Detectolab

Model EDU-7080

Investigate, analyze, decipher and solve the crime! Over 65 activities with fingerprints, secret messages, chromatography, cipher codes, identity detection and more... Kit includes 30X microscope and necessary lab equipment.

ELENCO

150 Carpenter Avenue

Wheeling, IL 60090

(847) 541-3800

Website: www.elenco.com

e-mail: elenco@elenco.com

Copyright © 2012, 2010 by Elenco®Electronics, Inc., all rights reserved. No part of this book shall be reproduced by 753292 any means; electronic, photocopying, or otherwise without written per mission from the publisher.

REV-E Revised 2012

Project 526

-1-

Table of Contents

Basic T roubleshooting 1 Parts List 2 About the Two-Spring Socket (?1) 3

About Your Snap Circuits®Parts 4

Advanced T roub leshooting 4

DO’s and DON’Ts of Building Circuits 5 Project Listings 6, 7 Projects 512-692 8 - 84 Other Fun Elenco®Products 85 - 86