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+# Inventory
+
+## Power
+Powermaster 24VAC 1AMP AC Power Supply 2.1MM Plug
+12v dc 1amp powerpack
+12vac 500mA powerpack
+
+## Tools
+2C53T 3-in-1 Handheld Oscilloscope, Multimeter & Generator
+Universal Crimping Pliers - 1.6 to 2.5mm Size Contacts - PA-21
+ENGINEER Precision Wire Stripper for Thick Wires (AWG24, AWG22, AWG20, AWG18, AWG16, AWG14, AWG12) PA-07 Made in Japan
+ENGINEER precision mini/micro side cutters, professional grade, ESD safe with hardened carbon steel jaws (PCB side snips). Made in Japan. ns-06
+
+## Construction
+Hook-Up Wire - Assortment (Solid Core, 22 AWG)
+Brass M2.5 Standoffs 16mm tall - Black Plated - Pack of 2
+Large Acrylic Offcut
+JST-PH 2 Pin Female Connector
+Professional Solderless Breadboard BB400 - 400 tie points (Metal Backing Plate)
+Terminal Barrier Panel with Clear Cover 4 Way
+
+## Components
+4Pcs 3W 8 Ohm Mini Loudspeakers 3 Watt JST-PH2.0 Interface Micro Speaker for Arduino
+Thin Speaker - 4 Ohm, 2.5W, 28mm
+2.5 mm JST XH-Style Shrouded Male Connector: 2-Pin, Right Angle (4-Pack)
+Panel Mount 2.1mm DC barrel jack
+Adafruit TLV320DAC3100 - I2S DAC with Headphone and Speaker Out
+
+## Capacitors
+60 top quality prime spec greencaps From 0.001uF to 0.22uF, all 100V.
+60 top quality prime spec 50V working ceramics. from 10pF to 0.1uF.
+
+## Resistors
+1/4 Watt
+Carbon Film
+5% Tolerance
+
+25x
+0Ω
+1.5Ω
+4.7Ω
+10Ω
+47Ω
+100Ω
+220Ω
+330Ω
+470Ω
+680Ω
+1kΩ
+2.2kΩ
+3.3kΩ
+4.7kΩ
+10kΩ
+22kΩ
+47kΩ
+100kΩ
+330kΩ
+1MΩ
+
+Potentiometer B1K 2K 5K 10K 20K 50K 100K 500K 1M
+
+3 Pcs 10K Thermistor Temperature Sensor Probe 3950 NTC
+
+## Voltage Regulators
+Voltage Regulator 5V (7805)
+Voltage Regulator 3.3V (LD1117)
+7805 7809 7812 7815 7905 7912 7915 LM317
+
+## ICs
+555 Timer - General Purpose Timer IC
+LM358AN Dual Operational Amplifier
+Op-Amp - LM258P (Through-Hole)
+10x TL072CP Operational Amplifier
+
+## Transistors
+TIP120 Power Darlington Transistors - 3 pack
+5 x PN2222 NPN
+5 x PN2907 PNP
+S9012  (10 units)
+S9013  (10 units)
+S9014  (10 units)
+S9015  (10 units)
+S9018  (10 units)
+A1015  (10 units)
+C1815  (10 units)
+A42    (10 units)
+A92    (10 units)
+2N5401 (10 units)
+2N5551 (10 units)
+A733   (10 units)
+C945   (10 units)
+S8050  (10 units)
+S8550  (10 units)
+2N3906 (10 units)
+2N3904 (10 units)
+
+## Fun kit
+1pcs Power Supply Module WARNING:
+1pcs 830 tie-points Breadboard
+1pcs 65 Jumper Wire 140pcs
+Solderless Jumper Wire 20pcs
+Female-to-male Dupont Wire
+2pcs Pin header (40pin)
+1pcs Precision Potentiometer
+2pcs Photoresistor
+1pcs Thermistor
+5pcs Diode Rectifier (1N4007)
+5pcs NPN Transistor (PN2222)
+1pcs IC 4N35
+1pcs IC 74HC595
+1pcs Active Buzzer
+1pcs Passive Buzzer 10pcs
+Button (small) 10pcs
+22pf Ceramic Capacitor 10pcs
+104 Ceramic Capacitor
+5pcs Electrolytic Capacitor (10UF 50V)
+5pcs Electrolytic Capacitor (100UF 50V) 10pcs
+White LED 10pcs
+Yellow LED 10pcs
+Blue LED 10pcs
+Green LED 10pcs
+Red LED
+1pcs RGB LED 10pcs
+Resistor (10R) 10pcs
+Resistor (100R) 30pcs
+Resistor (220R) 10pcs
+Resistor (330R) 10pcs
+Resistor (1K) 10pcs
+Resistor (2K) 10pcs
+Resistor (5K1) 10pcs
+Resistor (10K) 10pcs
+Resistor (100K) 10pcs
+Resistor (1M)
\ No newline at end of file
diff --git a/etc/vco-bom.md b/etc/vco-bom.md
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+# mki x es.edu VCO — Bill of Materials
+
+Check kit contents against list. In box also: PCB, panel, power cable, assembly sockets.
+
+## Resistors
+- [ ] 1M — x2
+- [ ] 100k — x9
+- [ ] 68k — x2
+- [ ] 47k — x1
+- [ ] 33k — x1
+- [ ] 14k — x1
+- [ ] 1k5 — x1
+- [ ] 1k — x2
+- [ ] 10 — x2
+
+## Thermistors
+- [ ] 10k — x4
+
+## Capacitors
+- [ ] 47 µF (electrolytic) — x2
+- [ ] 1 µF (1J/film) — x1
+- [ ] 100 nF (104/ceramic) — x5
+- [ ] 2.2 nF (2n2/film) — x1
+
+## Diodes
+- [ ] 1N4148 (signal) — x1
+- [ ] SB140 (schottky, or e.g. 1N5818) — x2
+
+## Transistors
+- [ ] BC548 (NPN) — x1
+- [ ] BC558 (PNP) — x1
+
+## Trimmer Potentiometer
+- [ ] 1k (W102) — x1
+
+## Potentiometers
+- [ ] 100k (B104) — x3
+- [ ] 250k (B254) — x1
+- [ ] 1M (B105) — x1
+
+## Jack Sockets
+- [ ] Switched mono (black) — x5
+
+## Chips
+- [ ] TL074 (quad op amp) — x1
+- [ ] CD40106 (hex schmitt trigger inverter) — x1