Meowsic Keyboard Output Jack

by randofo in Circuits > Audio

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Meowsic Keyboard Output Jack

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When Wilgubeast told me about the supremely annoying Meowsic Keyboard that played cat meows instead of tones, I knew I had to have one. Two days before Christmas I obsessively tracked it down to Target. I then obsessively visited five stores overrun with tumultuous hordes of holiday shoppers until I finally found a store that still had 3 in stock. I snatched one and headed immediately for the register. The checkout clerk, assuming this was surely a gift for a small child, asked if I wanted a bag in which to hide it. I told him it was not necessary. I knew the truth. I was a grown man buying a meowing cat keyboard with the intent of modifying it to play loudly through a distortion pedal during an underground rock show at Frenzy's house in Oakland.

The show went about as well as one might expect it would when someone is playing a meowing cat keyboard through a distortion pedal and a megaphone. We tried people's patience. I think our band may only have 8 lives left.

Nonetheless, I would be remiss if I didn't show you how to add an output jack and volume knob such that you too can use it to make a terrible racket at underground rock shows in Oakland.

You Will Need

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Go get stuff:

- Meowsic Keyboard
- 100K potentiometer
- 100K resistor
- 10uF capacitor
- SPDT toggle switch
- 1/4" mono jack
- A knob
- shrink tube (or electrical tape)

Open

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Open up the Meowsic Keyboard and make sure not to lose any of the (many many) screws.

Drill

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Drill a 3/8" hole in the top of the cat's head for the 1/4" jack.

Drill another 9/32" hole about an inch to the side of the first hole for the potentiometer. To keep the potentiometer from spinning in place, it helpful to drill another 1/8" hold just to the side to catch the little mounting tab.

Finally, drill a 1/4" hole about an inch to the side of the potentiometer for the SPDT switch.

Wire It Up

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To make the circuit, you will have to cut in half the wire that is connected to the + terminal on the speaker. The half connected to the circuit board will be extended and connect to the center terminal on the switch. The half connected to the speaker will be connected to one of the outer terminals.

The 100K resistor will bridge the outer terminal of the switch to one of the outer terminals of the potentiometer. The other outer terminal of the potentiometer will be connected to ground from the keyboard's power supply.

The positive side of the 10 uF capacitor connects to the center terminal of the potentiometer and bridges to the signal tab on the audio jack (where the negative terminal connects).

The barrel of the jack also connects to ground.

For more info, check out the schematic in the final picture of the series. To learn how to read schematics, check out the Basic Electronics instructable.

Clean Up

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Glue any loose components in place with hot glue and cover up any exposed electrical connections that may shift about with electrical tape.

Case Closed

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Refasten all of the screws that you loosened earlier.

Knob

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Finish it up by affixing a knob to your potentiometer.

Rock

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Take your keyboard, gather your bandmates, go forth, and make a terrible racket at underground rock shows.

Pictured is the band AIDS Walk (trying to look serious) moments before making a terrible racket.