CORRECTIONS & CLARIFICATIONS FOR YOUR SNAP CIRCUITS MANUALS

Front cover: Not all versions have enough parts to build the circuit shown, project 58 should be shown.
Project 15: this circuit does not always work, see Rev F for revised circuit.
Project 43: Make the connection mentioned with a jumper wire, not lamp L1.
Project 65: In rare cases this project may not work; see Rev F for revised circuit.
Project 73 – Near end of text change “in the across its terminals” to “in the coil and a voltage across its terminals.”
Project 84 – The circuit drawing is incorrect; see Rev F for revised circuit.
Project 85: Reference in text should be to project 84, not 89.

Rev D:

Page 6 – On point 6, B2 should be A1, D2 should be C1, B4 should be A3, and D4 should be C3.
Project 11 – If the fan doesn’t fly off even with new batteries then try pressing the switch several times rapidly when it is at full speed.
Projects 41-43 – You can make the new connection by using lamp L1 (on model SC-100 there is no 3-snap available for this).
Projects 56 and 59 – Some new types of fluorescent lights use electronic ballast to produce a constant light, and will not create the strobe effects described.
Project 68 – If this project doesn’t work, swap the locations of RP and S2.
Project 71 – Add “after a few seconds” to the end of the first sentence.
Project 83 – The text was clarified in the Rev E manual.
Projects 84-85 – These circuits do not always work, and were revised in the Rev E manual.

Rev C:

Parts list should say there are three 1-snaps, six 2-snaps, and three 3-snaps; not one of each.
Project 4 – Resistor cannot snap onto speaker as shown, remove the 1-snap to correct.
Project 10 – The red snap jumper creates a short circuit, so make the upper connection to U2 on level 2 and replace the 3-snap above it with the 100Ω resistor. Also, the 2-snap across U3-SP should be on level 3 and the 2-snap across SP-L1 should be on level 2.
Project 15 – Does not properly snap together, remove the 1-snap to correct.
Project 27 – "V" (near U2) should be "Y".
Project 40 – "V" (near U2) should be "Y".
Project 53 – Does not properly snap together, place the resistor on level 2 and move the 2-snap across U2-SP to level 3 to correct.
Project 71 – Base grid location C3 should be marked as point C, which is referred to in the text.
Projects 72 & 73 – Base grid locations A1 and C1 should be marked as points A and B, which are referred to in the text.
Project 76 – Remove “in the” from the 6th line of the text.
Project 79 – This circuit does not work well and was re-designed in Rev D.
Page 46 – The reference to page 25 should say page 28 for project 55; the reference to page 26 should say page 29 for project 57.

Experiments 102-305 manual:

[The manual revision is indicated on the bottom right of the cover. If you have an older version then you can view Rev F at

http://manuals.elenco.com/manuals/sc-300 102-305.pdf

Rev F:

There are no changes.

Rev E:

Project 111 – R4 is being replaced, not R5.
Project 112 – R4 is being replaced, not R5.
Project 123: The resistor at left is R3.
Project 180 – Place the fan on the motor.
Project 182 – Replace the 100Ω resistor (R1), not the 3-snap wire.
Project 219 – The objective and second sentence should refer to the speaker making sound, not the LED flashing.
Project 253 – The text should refer to lamp L1, not L2.
Project 263: Flip C4 for best performance.
Project 281: Flip C4 for best performance.

Rev D:

Project 109 – The text should refer to lamp L2, not L1.
Project 123 – Add a 2-snap across base grid locations E5-E6.
Project 139 – In the drawing, R1 should be R3.
Project 174 - This is the same circuit as project 102. See Rev-F for revised circuit.
Project 199 – This circuit does not always work, change D2 to C3 (+ on left) to fix.
Project 215 – The unmarked resistor on the left is R5.
Project 219 – This circuit does not always work. See Rev-F for revised circuit.
Project 253 – Add a 1-snap at base grid location E4.
Project 265 – This circuit does not always work. See Rev-F for revised circuit.
Project 277 – This circuit does not always work. See Rev-F for revised circuit.
Project 279 – Add a 1-snap at base grid location C3, level 2.
Project 280 – The 4-snap is on level 2, not level 1.
Project 288 – See Rev -F for an improved circuit, with better sound quality.
Project 296 – The resistor on level 2 is the 1KΩ (R2).

Rev C:

The project listing on page 7 incorrectly refers to project 233 as Electronic Golf Game, it should say Mind Reading Game.
Project 102 – Text line 2 should say 100, not 1K.
Project 104 – 2-snaps at F1-F2 and F2-F3 should say level 1 and level 3, respectively.
Project 134 – The circuit drawing is incorrect, replace variable resistor RV with PNP transistor Q1.
Project 151 – Three 2-snaps have the level marked incorrectly: D7-E7 should be on level 2, E7-F7 should be on level 3, and F7-F8 should be on level 2.
Project 158 – This project calls for five 3-snaps when only four are available, so replace the 3-snap across base grid locations G7-G9 with a 4-snap across G6-G9.
Project 164 – Change first line of 2nd paragraph to say: “Now turn off the slide switch. Repeat the test with the slide switch off; you’ll notice the LED goes out much faster after you release the press switch.”
Project 165 – In the second paragraph, (C4) should be (C5).
Project 177 – Second sentence should say: “Blowing hard into the microphone turns off the light briefly.”
Project 178 – Resistor R5 is on level 3, not level 2.
Project 180 – Capacitor C2 cannot be placed next to the speaker as shown. Remove the 1-snap from the speaker to correct this; C2 can be mounted between levels 3 and 4 on this circuit.
Project 185 – Part of the 3rd sentence should say: “appears to be on”, not “appears be on”.
Project 188 – Change “(C3, in either orientation)” to “(C3, plus side on right)”.
Project 197 – There should be a 2-snap connecting transistors Q1 and Q2.
Project 198 – Make these changes to improve performance: replace R5 with RV, remove 1-snap and 3-snap at A3-A5 and place jumper wires at these points, place 3-snap at E1-E3.
Projects 217 and 219 – The resistor cannot fit onto speaker as shown. Shift the resistor to level 2 and the 2-snap across grid locations D3-D4 to level 3, move the 1-snap to D3.
Project 225 – Text should say “Q2”, not “U2”.
Project 226 – Change “get” to “got” in line 3, and change “press press” to “press the press” in line 6.
Project 230 – “C5” should be “CV”.
Project 232 – The text should say: “Use the circuit from project 228 shown above, but change the 1KΩ resistor (R2) to the 100Ω resistor (R1). While holding down the press switch (S2), move the slider on the adjustable resistor (RV) around. When the slider is near the 100Ω resistor you won’t hear any sound, but the circuit is still working. This oscillator circuit is making sound waves at a frequency too high for your ears to hear. But your dog may hear it, because dogs can hear higher frequencies than people can.”
Project 245 – Change 4th sentence to say: “Any loud sound or vibration causes the whistle chip to produce a small voltage, which activates the circuit.
Project 253 – There should be a 1-snap at base grid location E4, on level 1.
Project 262 – Flip the motor around, so the “+” side is down.
Project 276 – The drawing shows the wrong circuit, and is corrected in Rev D.
Project 278 – The 4-snap on the left is on level 2, not 3.
Project 279 – The speaker is on level 3, not 2.
Project 284 – Once activated, the sound stays on until you turn off the switch.
Project 300 – There should be a 1-snap at G7.

Experiments 306-511 manual:

[The manual revision is indicated on the bottom right of the cover. If you have an older version then you can view Rev C at

http://manuals.elenco.com/manuals/sc-500 306-511.pdf

Rev C:
There are no changes.

Rev B:
Project 306 – Set the control lever on the adjustable resistor (RV) toward the left when you start.
Project 343: S1 should be under the 2-snaps.
Project 458 – Base grid location D1 should be labeled as point A, not point D.

Rev A:
Project 306 – This circuit does not work very well. See Rev-B for revised circuit.
Project 307 – Remove first paragraph of text.
Project 312 – D3 does not fit properly on U6. You can make it fit properly by replacing the 4-snap with three 2-snaps.
Project 317 – This circuit does not work very well. See Rev-B for revised circuit.
Project 318 – This circuit may damage the SCR so replace the 3-snap wire with the 1K resistor (R2).
Project 323 – This circuit is a 3mA meter, not a 1mA meter.
Project 342 – The text should say 7 seconds, not 10 seconds.
Project 343 – In the text, R4 should be R2.
Project 358 – The text mentions current paths shown by arrows in the drawing, which are not in the drawing. There should be an arrow in the upper-left part of the circuit showing a clockwise current, and an arrow in the lower-left part of the circuit showing a counter-clockwise current.
Project 383 – Use the circuit from project 382, not project 381.
Project 384 – Modify the circuit to add resistor R1 in series with LED D1, or D1 may be damaged.
Projects 386 and 387 – Rev-B has a better explanation of how these circuits work.
Project 393 – You hear the machine gun when the room is bright, not dark.
Project 422 – You are replacing the 100mF capacitor with the 10mF capacitor.
Project 434 – The text should say 15 seconds, not 10 seconds.
Projects 440-443 – These are the same as projects 411-418, see Rev-B for revised circuits.
Project 466 – The text mentions current paths shown by arrows in the drawing, which are not in the drawing. There should be an arrow in the upper-left part of the circuit showing a counter-clockwise current, and an arrow in the lower-left part of the circuit showing a clockwise current.
Project 476 – Number 0 will be displayed, not number 4.
Project 492 – The text should say to clap your hands next to the whistle chip, not the speaker.

(no Rev):
On page 4, “the circuit.” should be added at the end of the description of the 7-segment LED display.
Project 307 - Ignore the first paragraph.
Project 312 - D3 does not fit properly on U6, you may let this part hang loose on one side and make the connection with a jumper wire.
Project 318 - Replace 3-snap with 1K resistor.
Project 325 – In last paragraph, replace “/” with “part”.
Project 338 – Add segment B, remove segment D.
Project 339 – Add segment B.
Project 340 – After “across points A & B” add “(use a jumper wire to complete the connection)”.
Project 343 - Change resistor from 10K to 1K.
Project 346 – The text is incorrect, it should say 1K (R2) and “increasing the resistance decreases”.
Projects 347 & 399 are the same, this will be corrected when we revise this manual.
Project 354 - Uses six 3-snaps but only 4 are available, use the snap jumpers as substitutes. Line 3 of the text should say C3, not C5.
Project 380 – Use the circuit from project 379, not 377.
Project 381 – On line 5 of the second paragraph, “is turned on” should be “is turned off” and “C5” should be “C4”.
Project 384 - Does not work as described, add 100Ω resistor in series with red LED to correct.
Project 387 – A jumper cable should be shown connecting points A and B.
Project 398 – Uses five 3-snaps but only 4 are available, use the antenna or a jumper wire as a substitute.
Project 410 - 3-snap across C1-E1 should be layer 2.
Projects 411 to 418 – Replace the 3-snap across base grid locations A1-C1 with the photoresistor. Also, the text should say that the display is flashing when you turn on the switch, and goes off when you cover the photoresistor. You can add sound to this circuit by connecting the whistle chip across A2-C2.
Project 414 – Remove “D”, add “G”.
Project 419 - Place whistle chip on top of the transformer on the left side.
Project 422 – Replace text with “Use the circuit in project 419, but replace the 100mF capacitor (C4) with the 10mF capacitor (C3). “
Project 423 - Replace text with “Use the circuit in project 419, but replace the 100mF capacitor (C4) with the 470mF capacitor (C5). “
Project 424 - Replace text with “Use the circuit in project 419, but replace the 100mF capacitor (C4) with the 10mF capacitor (C3) and connect the whistle chip across points B & C. You can also connect the whistle chip across points C & D.”
Project 425 - D3 does not fit properly on U6, you may let this part hang loose on one side and make the connection with a jumper wire.
Project 435 – Add whistle chip at base grid locations A2-C2, level 3.
Project 440 – Remove the first sentence of the text. Add whistle chip at base grid locations A2-C2, level 3.
Project 447 - Add speaker and two 2-snaps on right side of transformer.
Project 457 – Do not use the LED in this circuit since it may get damaged. Use only the 6V lamp.
Project 471 – Add segment C.
Project 473 – Add segment A, remove segments D and G.
Project 489 – Replace last sentence with “After the music stops, hold down the press switch (S2) to make it continue.”
Project 501 – Change the 3-snap across C2-C4 (over display D7) to the light-blue color and change the “3” on it to a “G”.
Project 508 – Remove the 3rd sentence about making sound.

Experiments 512-692 manual:

[The manual revision is indicated on the bottom right of the cover. If you have an older version then you can view Rev C at

http://manuals.elenco.com/manuals/sc-750 512-692.pdf

Rev C:
There are no changes.

Rev B:
(There is no revision A.)
Project 536 – Ignore the last paragraph of the text; it refers to a circuit that is not in your manual.
Project 542 – Ignore the last paragraph, since resistor R1 limits the current.
Project 549 – Red LED D1 should be under the blue snaps.
Project 568 – The 1-snap at C5 is on level 1, not level 2.
Project 595 – The 3-snap at C6 should be under capacitor C5.
Project 601 – Do not place the fan on the motor.
Project 613: Uses three 4-snaps but you only have two. Replace the 4-snap at D6-G6 with the red jumper wire; this also removes three 1-snaps.
Project 615 – This project uses seven 1-snaps, but only six are available. The 1-snap at E6 on level 4 may be omitted.
Project 673 – Use the 6V lamp (L2) instead of the 2.5V lamp (L1).
Project 674 – Use the 6V lamp (L2) instead of the 2.5V lamp (L1).
Project 677 – Remove “(using a spacer on point B)”.
Project 692 – If the lamp never turns on then replace resistor R2 with resistor R1.

(no Rev):
Page 3 – Remove “don’t” from last sentence of 3rd paragraph.
Project 520 – The part beneath the press switch is transistor Q1.
Project 523 – R4 is on level 2, not level 1.
Project 526 - If the motor does not spin then give it a push with your finger to start it or remove the fan.
Project 538 – The text was revised in Rev-B to be simpler.
Project 550 - The green LED is dim even in sunlight. See Rev-B for revised circuit.
Project 558 – There should be a jumper wire connecting point A on the alarm IC (below the 4-snap) to point B.
Project 577 – This circuit does not work very well. See Rev-B for revised circuit.
Project 581 – This circuit uses U1, not U2.
Project 584 – The text should refer to U4, not U2.
Project 592 – Remove the 2-snap at E5-E6.
Project 605 - Some text references to segment E should be C and some to segment C should be E.
Project 606 – Rev-B has a revised circuit.
Project 607 – There is no 1-snap at base grid locations B6 or E6.
Projects 607, 608, 610, 612-615, 632, 640, 650, 651 – Note that some wires cross directly above one another with little separation but are not connected, this wiring arrangement gives the mistaken impression that these points are connected. For example, the red and black jumper wires are connected to the 7-segment LED display but not connected to the 3-snap wires directly above them. These circuit drawings were revised in Rev-B.
Project 619 – This circuit may damage L1. See Rev-B for a revised circuit.
Project 620 – This circuit may damage L1. See Rev-B for a revised circuit.
Project 621 – Remove RP and shift S2 to RP’s location.
Project 681– remove the 3rd paragraph of text.

Experiments PC1-PC73 manual:

[The manual revision is indicated on the bottom right of the cover.]

http://manuals.elenco.com/manuals/CI-73.pdf

Rev B:
There are no revisions at this time.
(There is no revision A.)

(no Rev):
Page 1 – The note to Mac users is incorrect, there is no Mac compatible software available at this time.
Page 4, Note A – pages 9-11 should be 8-10 and page 3 should be 4.
Project PC1 – This circuit does not always work, change D2 to C3 (+ on left) to fix.
Project PC10 – In the last paragraph, the Light and Sounds project is PC4 and on page 16.
Project PC11 – In the last paragraph, the Microphone project is PC14.
Project PC24 – This circuit does not always work. Remove C3, replace WC with C1, and place L2 in parallel with SP to fix (project 265 in the Rev-F Experiments 102-305 manual shows the revised circuit).
Project PC25 – If the circuit does not make any sound, then replace R2 with L2.
Project PC34 – The circuit works better if you replace R5 with R4.
Project PC52 – You are placing C5 on top of C4, not C3.

RC Snap Rover:

http://manuals.elenco.com/manuals/SCROV_10.pdf

In rare cases, the buzzer (W1) will not make sound or will sound abnormal in some projects. If this occurs, change your circuit as follows:
Project 1 – Move the 100mF capacitor (C4) from base grid points E2-E4 to points C2-C4 (“+” on point C4), remove the 1-snap at point E1, and now the 2-snap at E1-E2 is on level 2.
Project 5 – Add the unused 100mF capacitor (C4) across base grid points A4-C4 (“+” on point A4, which will be lower than the other side).
Project 7 – Swap positions of the buzzer (W1) and the LED (D4).
Project 12 – Move the gray jumper wire from base grid point D9 to F9.
Project 14 – Replace the 100Ω resistor (R1) across base grid points A6-A8 with a 4-snap wire across A5-A8.
Project 17 – Replace the 1KΩ resistor across base grid locations B10-D10 with a 100mF capacitor (C4, “+” on point B10).
Project B2 – Swap positions of the buzzer (W1) and the LED (D4).
Project B3 – Replace the buzzer (W1) with the LED (D4, “+” on top).

Snaptricity:

http://manuals.elenco.com/manuals/scbe75.pdf

This product used a new motor to extend battery life, but some projects are changed (manual will be corrected in the next revision):
Project 12 – Remove “a lot” from operation text (voltage drops more than with lamp, but not a lot more).
Project 30 – Typical motor resistances in table should be 10 ohms with fan and 40 ohms without fan.
Project 55 – In operation text, add “or go out” after “lamps get dim”.
Project 59 – This project only works if you have the old-style motor, so use the following circuit in its place. Place the thin rod inside the electromagnet and press the switch. When the slide switch positions are set to their B positions, the motor will spin a little slower, the thin rod will be a little lower, and the lamps will be very dimly lit. You may have to give the motor a push to get it started.

SC-100R Student Guide (Junior):

Page 21 – The experiment does not work with all fluorescent lights because some new types use an electronic ballast and they also produce a constant light.
Page 41: Projects 36-37 use the motor and alarm IC to control the space war IC.
Page 42, left box – Projects 84-85 are different in some manuals (Rev-E or later), in these sound effects from the music and alarm ICs are combined with the motor.
Page 45 – Ground definition is duplicated.
Page 46 – In the definition for solder, “360 degrees” should be “500°F”.

SC-300R Student Guide:

Page 4, yellow box – Remove “them” from first sentence so it reads correctly.
Page 27, lower right box – Some project manuals have a slightly different circuit for project 276; they work the same way.
Page 28, top box – Some project manuals have a slightly different circuit for project 174; they work the same way.
Page 47, top box – Some project manuals have a slightly different circuit for projects 130-131 (R2 was changed to R1). Use the circuit shown in your Student Guide (with R2).
Page 47, lower left box – Some project manuals have a slightly different circuit for project 253; they work the same way.
Page 48 – Some project manuals have slightly different circuits for projects 261 (upper left box) and 300 (lower right box); they work the same way.
Page 49, top left box – Some project manuals have a slightly different circuit for project 302; they work the same way.
Page 56, lower box – “Can” should be “to” in the last sentence. Some project manuals have a slightly different circuit for project 199; they work the same way.
Page 57, lower box – The reference to project 198 in the first sentence does not apply to all project manuals.
Page 58, lower box – Some project manuals have a slightly different circuit for projects 185-189; they work the same way.
Page 63, lower left box – The bottom entry is for projects 36-37.
Page 64, left box – Projects 84-85 are different in some manuals (Rev-E or later), in these sound effects from the music and alarm ICs are combined with the motor.
Page 65 – Project 277 uses the whistle chip, not the photoresistor.
Page 68, lower left box – The experiment does not work with all fluorescent lights because some new types use an electronic ballast and they also produce a constant light.
Page 72, top box – In some project manuals (Rev-E or later) project 198 is a radio transmitter that lets you hear your voice on the radio.
Page 72 – in quiz question 3 the answer is A, not D.
Page 76 – Ground definition is duplicated.
Page 77 – In the definition for solder, “360 degrees” should be “500°F”.

SC-500R Student Guide (Extension):

Note: If your meter (M2) has a switch on it, use the LOW (or 10mA) setting for all circuits in this booklet.
Page 3, upper box – Some project manuals have a slightly different circuit for project 323; they work the same way.
Page 5, yellow box – For the transformer schematic symbol, “Inductance” should be beneath “Higher” and “Lower”.
Page 6 – Some project manuals have slightly different circuits for projects 358 and 359; they work the same way.
Page 11, top box – Some project manuals have a slightly different circuit for project 307; they work the same way.
Page 12 – Item 2 of the summary should say: In a transformer, the side with less loops of wire has higher current while the side with more loops of wire has higher voltage.
Page 14, lower box – The markings on the resistor are hard to see, it is the 5.1KΩ (R3).
Page 18, lower box – In some manuals projects 444-446 are timer circuits that do not use the 7-segment LED display.

Teacher’s Guide:

Page 11 – In question 3.15, ignore the reference to the adjustable resistor, and the photoresistor in branch A of the circuit drawing should have arrows next to it like the one in the D branch.
Page 20 – The answer to question 1.15 is B, not C. The answer to question 1.18 is TRUE, not FALSE.