Gadget Freak Case #105: KeyCom Helps Keep Everybody in the Same Key

DN Staff

July 16, 2007

4 Min Read
Gadget Freak Case #105: KeyCom Helps Keep Everybody in the Same Key

There was dissonance in the church when the pianist and other musicians had to hunt for the key their Music Leader was playing in. Dick's gadget took the guesswork out of the guitar, the meandering out of the mandolin and the pondering out of the piano. The Music Leader communicates the key to the others by setting the display on his Sending Unit via pushbutton or the foot switch, and the Remote Units replicate that display for everyone else. Now, they're all in one A chord (or F, or C, or...).

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Amt

Part Description

Allied Part #

1

7-Segment Display, Common Anode, Right Decimal, 0.8 inch

782-0570

1

7-Segment Display, Common Anode, Right Decimal, 13 mm

431-0048

16

1N914 Diode

431-0618

13

2N7000 N-channel MOSFET

568-0741

4

2N2222 NPN transistor

248-1004

4

1N4004 rectifier

266-0004

1

1N4742A Zener, 12V 1W

431-0332

1

CD4001 CMOS Quad 2-NOR

735-0960

1

CD4002 CMOS Dual 4-NOR

735-1065

1

CD4013 CMOS Dual D-flop

735-1325

1

CD4051 CMOS 8-ch MUX/DEMUX

735-0989

1

CD4070 CMOS Quad XOR

735-1002

1

CD4073 CMOS Triple 3-AND

735-1343

1

CD4081 CMOS Quad 2-NAND

735-1015

1

CD4093 CMOS Quad 2-NAND, Schmitt Trigger

735-1023

2

CD4099 CMOS 1 of 8 Decoder/Latch

735-2444

1

CD4516 CMOS 4b Up/Down Counter

735-1038

1

MC14526 CMOS 4b Presettable Down Counter

568-0877

2

RJ25 Right Angle jack w/ panel stops

374-5770

1

3.5 mm stereo phone jack (needs nut & washer)

283-0352

1

3.5 mm stereo phone plug w/ strain relief

283-3291

2

Push-button switch, NO, bushing mount w/ nut & washer

250-3241

Red Tail light tape (Automotive store item) Additional hardware & passive components, See Text

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