The Pearl Box:Definition - This is a box that may substitute for many boxes
which produce tones in herts. 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 in order to build The Pearl Box:
C1, C2::::::::.5mf or .5uf ceramic disk capacitors
Q1::::::::::::NPN transistor (2N2222 works best)
S1::::::::::::Normally open momentary SPST switch
S2::::::::::::SPST toggle switch
B1::::::::::::Standard 9-Volt battery
R1::::::::::::Single turn, 50k potentiometer
R2:::::::::::: " " 100k potentiometer
[R3:::::::::::: " " 500k potentiometer
R4:::::::::::: " " 1meg potentiometer
SPKR::::::::::Standard 8-ohm speaker
T1::::::::::::Mini transformer (8-ohm works best)
Misc.:::::::::Wire, solder, soldering iron, PC board or perfboard, box to
contain the completed unit, battery clip
Instructions for building The Pearl Box:
========================================
Since the instruction are EXTREMELY diffucult to explain in words, you will be given a schematic instead. It will be quite diffucult to follow but try it any
way. There is also a Hi-Res picture you can get that shows the schematic in
great detail.
(Schematic for The Pearl Box)
+--------------+------------+---------+
! ! \ +--S1----
C1 C2 \ SPKR
! ! + +--------
+ + ----+T1 +
!\ +-----------+----------+
! b c-----!
! Q1 !
! e--S2--+ !
! ! !
! B1 !
! ! !
! +-----------+
!R1 R2 R3 R4!
/\/\ /\/\ /\/\ /\/\
+--+ +--+ +--+
*again as good as it gets
Now that you are probably thourghly 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 peice 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 alot 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.
Step 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)
Step 2: Hit the pushbutton switch and VWALA! You have the tone. If you don't
have a tone recheck all connections and schematic.