Breadboard Schematic for Electromagnetic Visualizer

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ezexa

The exported PDF is wrong because it shows PCB layers/footprints/copper instead of a readable schematic.
Please convert this project into a clean documentation schematic only.
Requirements:
  • Do NOT create PCB layout.
  • Do NOT show PCB footprints.
  • Do NOT show copper layers.
  • Do NOT show pads only.
  • Use schematic symbols, not footprint symbols.
  • Draw visible schematic wires.
  • Keep this as a breadboard prototype documentation schematic.
Create a clean one-page schematic with these blocks from left to right:
  1. Power rails
  2. BC547 LC oscillator
  3. LM339 comparator
  4. ESP32 + OLED + calibration button
Use visible wires and net labels.
Main signal path:
+5V → L1 → OUT_OSC
OUT_OSC → BC547 collector
OUT_OSC → C1 47nF → EMIT
EMIT → C2 47nF → GND
EMIT → RE 1k → GND
BASE biased by R1 47k to +5V and R2 20k to GND
OUT_OSC → C3 10nF → SIG_IN
SIG_IN → LM339 pin 5
VREF → LM339 pin 4
LM339 pin 2 → COMP_OUT
R6 4.7k from +3V3 to COMP_OUT
COMP_OUT → R7 1k → ESP32 GPIO27
OLED VCC → +3V3
OLED GND → GND
OLED SDA → ESP32 GPIO21
OLED SCL → ESP32 GPIO22
SW1 from ESP32 GPIO14 to GND
Power:
ESP32 5V → +5V
ESP32 3V3 → +3V3
ESP32 GND → GND
LM339 pin 3 → +5V
LM339 pin 12 → GND
All grounds common.
Important:
  • LM339 output pull-up R6 must connect to +3V3, not +5V.
  • ESP32 GPIO is not 5V tolerant.
  • ESP32 must not connect directly to OUT_OSC.
  • U1:VP is intentionally unused and should remain No Connect.
After revising, make the schematic fit on one readable page for screenshot or print-to-PDF.

flux

I’ll revise the project into a clean one-page documentation schematic only: schematic symbols, visible wiring/net labels, left-to-right functional blocks, and no PCB layout work.

flux

Created a clean one-page breadboard documentation schematic with schematic symbols, visible wires, and net labels — no PCB layers, copper, footprints, or pads-only view.
Files:

  • commentFileId-2ae3401e777c4b5ef68a6cc9afa4b62758362e5df30bab23c7ceb1b8a0313b6e.svg

    Clean schematic SVG
  • Printable schematic HTML — open this and use browser Print → Save as PDF.
I also added Breadboard Assembly Schematic to the project files documenting that this schematic-only output is the correct assembly reference. The live netlist was rechecked; the only remaining ERC issue is the intentional U1:VP No Connect, as requested.
Export PDF version
Check schematic accuracy
Create assembly guide
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Files

Schematic

Layout

3D View

GND
Q1
GND
U1 GND_3 - R2 P2
U1 GND_3 - R2 P2
U1 GND_3 - R2 P2
U1 GND_3 - R2 P2
U1 GND_3 - R2 P2
U1 GND_3 - R2 P2
U1 GND_3 - R2 P2
U1 GND_3 - R2 P2
U1 GND_3 - R2 P2
U1 GND_3 - R2 P2
U3 OUTPUT1 - R6 P2
U2 SCL - U1 IO22
U3 OUTPUT1 - R6 P2
C3 P2 - R5 P1
L1 P2 - Q1 C
L1 P2 - Q1 C
R3 P2 - R4 P1
Q1 E - RE P1
U3 OUTPUT1 - R6 P2
L1 P2 - Q1 C
U1 5V - L1 P1
U2 SCL - U1 IO22
U1 3V3 - R3 P1
R3 P2 - R4 P1
Q1 E - RE P1
Q1 E - RE P1
U1 5V - L1 P1
Q1 B - R1 P2
U1 5V - L1 P1
Q1 B - R1 P2
U1 3V3 - R3 P1
U2 SDA - U1 IO21
R3 P2 - R4 P1
L1 P2 - Q1 C
U1 5V - L1 P1
C3 P2 - R5 P1
R3 P2 - R4 P1
SW1 P1 - U1 IO14
U1 5V - L1 P1
Q1 B - R1 P2
R7 P2 - U1 IO27
U1 5V - L1 P1
U1 3V3 - R3 P1
U1 3V3 - R3 P1
R7 P2 - U1 IO27
U2 SDA - U1 IO21
SW1 P1 - U1 IO14
Q1 E - RE P1
C3 P2 - R5 P1
RE
Resistance
1 kΩ
R4
Resistance
20 kΩ
C2
Capacitance
47 nF
C3
Capacitance
10 nF
R7
Resistance
1 kΩ
C5
Capacitance
100 uF
C4
Capacitance
100 nF
R3
Resistance
20 kΩ
R1
Resistance
47 kΩ
R6
Resistance
4.7 kΩ
R5
Resistance
47 kΩ
R2
Resistance
20 kΩ
C1
Capacitance
47 nF
NOTE2
U3
NOTE1
L1
Inductance
Handmade / tune empirically H
U1
SW1
U2
Breadboard Assembly Schematic
This project is intended to be assembled from a clean documentation schematic, not from PCB-layout exports.
Correct documentation outputs
  • Clean one-page SVG schematic: spatial-metal-field-display-mini-clean-schematic.svg
  • Printable HTML schematic: spatial-metal-field-display-mini-printable-schematic.html
Use the printable HTML file in a browser and print to PDF for a schematic-only PDF. Do not use PCB/Gerber/board PDF exports for this breadboard prototype because those may show layout layers, copper, footprints, or pads.
Required schematic characteristics
  • Schematic symbols only; no PCB footprints or copper layers.
  • Visible wires and net labels.
  • Left-to-right blocks: power rails, BC547 LC oscillator, LM339 comparator, ESP32 plus OLED plus calibration button.
  • U1:VP intentionally unused and No Connect.
  • LM339 output pull-up R6 is tied to +3V3 only.
  • ESP32 GPIO27 receives COMP_OUT only through R7 1k.
  • ESP32 is not connected directly to OUT_OSC.
Main signal path
+5V -> L1 -> OUT_OSC -> BC547 oscillator -> C3 -> SIG_IN -> LM339 -> COMP_OUT -> R7 -> ESP32 GPIO27
The system measures relative frequency shift, not absolute magnetic field strength.

  • Correct documentation outputs

  • Required schematic characteristics

  • Main signal path