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Summary of Contents for stereophonic AK-900
- Page 1 ELECTRONIC KEYBOARD MODEL AK-900 WARNING: CHOKING HAZARD - Small parts, not for children under 3 years of age. Assembly and Instruction Manual...
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Page 2: Tools Needed
Speaker, with plug-in connector to Circuit Board 520820 Battery Cover 626016 Battery Pad 626017 AK-900 Label 727000 Battery Wires, with plug-in connector to Circuit Board, short wire to 880012 battery contact spring, and long wire to battery contact clip TOOLS NEEDED... -
Page 3: Parts Identification
PARTS IDENTIFICATION Button Cushion w/ Piano Cushion w/ 12 Contacts 12 Contacts Piano Cushion w/ Button Cushion 13 Contacts w/ 2 Contacts White Piano Black Piano Key Clip Key Clip w/ 7 Keys White Piano Key Clip w/ 8 Keys Switch Spring Switch Ball Bearing Speaker Clamp... -
Page 4: Theory Of Operation
INTRODUCTION The AK-900 Electronic Keyboard is a electronic music system that you put together. It has 37 keys, 8 instrument sounds (piano, flute, violin, organ, French horn, banjo, music box, guitar), 8 tempo adjustable rhythms (pop music, disco, march, rhumba, tango, waltz, swing, ballad), 4 percussion effects (bass drum, close cymbals, open cymbals, indian snare drum), and 1 demonstration routine along with stereo, vibrato, and tempo effects. - Page 5 Fundamentals of Music What is Music? Music is when vibrations (creating sound waves) occur in an orderly and controlled manner forming a pattern with their energy concentrated at specific frequencies, usually pleasant to listen to. Noise is when the vibrations occur in an irregular manner with their energy spread across a wide range of frequencies, usually annoying to hear (static on a radio is a good example).
- Page 6 A3, G#4, D6, A#1, and E2. Your AK-900 Electronic Keyboard plays notes from C3 to C6, in order across the keyboard. (frequency in hertz and rounded off) Up to now, the musical measures of pitch and loudness have been discussed.
- Page 7 Now consider the following two tones, which differ slightly in frequency: If they are played at the same time then their sound waves would be added together to produce: Notice that the combined wave has a regular pattern of where the two tones add together and where they cancel each other out.
- Page 8 Tempo is a musical term which simply describes how quickly a song is played. The Electronic Keyboard Implementation: The AK-900 electronically creates sounds that closely resemble those from traditional musical instruments. A quick look at the schematic (a graphical representation of an electronic circuit) on page 17 will show the reader that the IC 9037 is the heart of the product.
- Page 9 Observe that IC 9037 is the only component in the AK-900 mounted directly on the printed circuit side of the board with no holes through the board; this is called surface-mounting and today many electronics products have ALL of their components surface-mounted due to its advantages in saving space (this was not a concern on the AK-900 due to the space required for the keys and buttons).
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Page 10: Assembly Instructions
ASSEMBLY INSTRUCTIONS 1. Take a look at each of the parts bags and compare to the Parts List. Be sure that nothing was damaged during shipping and handling. Contact Elenco Electronics if you have any problems. DO NOT contact your place of purchase as they will not be able to help you. - Page 11 4. Locate the Black and White Piano Key Clips (Bag #2). Place the White Clips into the inside of the Top Case (as shown in Figure Ea). There are 3 small pegs (one for each clip) on the inside for alignment. The tab at the end of each key must slide into its slot on the front of the Case (the “bottom of the keyboard”) so that it will not be visible (as shown in Figure Ea).
- Page 12 5. Locate the buttons (Bag #4). Attach the 4 Large Pink Button Contacts to the Large Pink Buttons as shown in Figure F. Now place the 4 Large Pink Buttons, the 8 Small Green Buttons, the 8 Small Orange Buttons, the 4 Medium Blue Buttons, and the 2 Small Pink Buttons into the inside of the Top Case as shown in Figure F.
- Page 13 6. Straighten the red LEDs (Light-Emitting-Diodes) on the Circuit Board so that they are standing straight up (they may have been bent to protect them during shipping). Place the Circuit Board into the Top Case, components side facing you, as shown (it is aligned using 8 tabs on one side and 2 tall screw holes on the other side).
- Page 14 7. Place the Speaker (Bag #5) in its slot next to the Circuit Board and plug its connector into the Circuit Board. The tab on the speaker connector should be facing the Speaker so that the connectors “lock” together. If the tab is on the wrong side then the Speaker will be wired incorrectly and will not work.
- Page 15 9. Connect the Battery Wires (Bag #5) to the Circuit Board by plugging in the connector (as shown in Figure J). The tabs on the connector should be facing the Speaker so that the connectors “lock” together. If the tabs are on the wrong side then the product will be wired incorrectly and will not work.
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Page 16: Operating Instructions
Adapter then you don’t need batteries). Remove the backing from the Battery Pad and stick it on the Battery Cover, then place the Cover in its slot on the Bottom Case to secure the batteries. Place the AK-900 Label in the center of the Bottom Case. -
Page 17: Troubleshooting Guide
8. Two tones, with frequencies of 250 Hz and 255 Hz and similar loudness, will produce a __________ when played together. 9. ________ is adjusted in the AK-900 by changing the rate at which a tone pattern is played from memory. 10. Long, thin copper traces connect electronic components on __________ __________ __________. -
Page 18: Schematic Diagram
SCHEMATIC DIAGRAM IC 9037 BLOCK DIAGRAM VIBRATO OSC1 OUT1 Oscillator Timing Divider Driver OSC2 KEY1 Tone1 Envelope Circuit ENV1 KEY2 Generator Direct Keyboard Envelope Circuit KEY36 Logic Tone2 ENV2 KEY37 Generator Rhythm OUT2 Driver Generator Matrix Percussion Control Key Generator D/A Output Logic Tempo... - Page 19 IC 9037 Pin Description Internal Pin No. Pin Name Description Connection 1, 2 C3, C4 NMOS Matrix control key scanning outputs 3 - 7 R4 - R0 CMOS Pull-High Matrix control key scanning inputs Direct key inputs 8 - 44 KEY1 - KEY37 CMOS Pull-High There are 22 full-scale and chromatic-key inputs for playing.
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Page 20: Glossary Of Terms
GLOSSARY OF TERMS Acoustics The science of designing rooms for best sound effects. Amplitude A measure of the strength of an electronic signal. Audio The range of sounds that can be heard by the ear. Bass Tones Low frequency sound, usually below 300 Hz. Beat A pattern in musical rhythm caused by 2 tones at different frequencies (usually close), so that they regularly form highs and lows in loudness. -
Page 21: For Further Reading
Rhythm The pattern of regular beat that a song has. Schematic A graphical representation of an electronic circuit. Semitones The division of notes within each overtone on the musical scale. Solder A metal that melts at temperatures between 400°F and 800°F; it is used to connect electronic components to each other or to copper traces on printed circuit boards. - Page 22 Here are some other exciting projects from Elenco you can build. SOLDERLESS KITS Talking Clock Kit 35mm Camera Kit with training course with training course Model AK-220 Model AK-540 This easy-to-build kit will teach you how electronic voices Now you can learn all about photography with our new are made.
- Page 23 All kits on this page require soldering. DELUXE KITS Stereo Cassette Kit Digital Roulette Kit with training course with training course Model AK-200 Model AK-300 Easy-to-build kit teaches you basic mechanical and This Digital Roulette Kit is just like the real thing. With a electronic circuits.
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