pearl box plans
The Pearl Box: Definition - This is a box that may substitute for many boxes which produce tones in hertz. The Pearl Box when operated correctly can produce tones from 1-9999hz. As you can see, 2600, 1633, 1336 and other crucial tones are obviously in its sound spectrum.
Materials you will need:
1.C1, C2:�mf or �uf ceramic disk capacitors
2.Q1.....NPN transistor (2N2222 works best)
3.S1.....Normally open momentary SPST switch
4.S2.....SPST toggle switch
5.B1.....Standard 9-Volt battery
6.R1.....Single turn, 50k potentiometer
7.R2.....Single turn, 100k potentiometer
8.R3.....Single turn, 500k potentiometer
9.R4.....Single turn, 1Meg potentiometer
10.SPKR...Standard 8-ohm speaker
11.T1.....Mini transformer (8-ohm works best)
12.Misc...Wire, solder, soldering iron, PC board or perfboard, box to contain the completed unit, battery clip
(the picture that explains this is hard to display on html. atleast for me . so if u want to know how to make this email me. i got a link to my email on the home page. sorry for the inconvenience)
Now that you are probably thoroughly confused, let me explain a few minor details. The potentiometer area is rigged so that the left pole is connected to the center pole of the potentiometer next to it. The middle terminal of T1 is connected to the piece of wire that runs down to the end of the battery.
Correct operation of The Pearl Box:
You may want to get some dry-transfer decals at Radio Shack to make this job a lot easier. Also, some knobs for the tops of the potentiometers may be useful too. Use the decals to calibrate the knobs. R1 is the knob for the ones place, R2 is for the tens place, R3 if for the hundreds place and R4 is for the thousands place. S1 is for producing the all the tones and S2 is for power.
1.Turn on the power and adjust the knobs for the desired tone.
(Example: For 2600 hz-R1=0:R2=0:R3=6:R4=2)
2.Hit the push-button switch and VIOLA! You have the tone. If you don't have a tone recheck all connections and schematic.
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