Highway to Undercity

total time (so far): 47.5 hrs

2025-06-17

Researched how guitar amps work
Researched components needed for a guitar amp
Researched how bluetooth works

Time spent: 2 hrs

2025-06-18

Found specific components to use
Made symbols & footprints for the components
Started researching how to make an amplifier circuit

Time spent: 3 hrs

2025-06-21

Fixed pin orientation of bluetooth module
Made v1 of schematic (partial reference design here)

Time spent: 7 hrs (yeah it was not easy :|)

2025-06-21

Footprints, footprints, footprints
First draft of PCB (awaiting review)
Minor edits to schematic

Time spent: 5 hrs

2025-06-22

Added distortion circuit
Started figuring out how SPICE simulations work

Time spent: 4 hrs

2025-06-23

Installed LTSpice
Built the circuit in LTSpice
Simulated the circuit
Tried a lot of different values for the components
Added an RC filter to the output
Still not working :|

Time spent: 6 hrs

2025-06-24

Fixed distortion circuit
Changed pre-amp stage
Added voltage cap (max ~1.9VPP now)
Changed to LDO for 9V to 5V conversion
Rebuilt schematic in KiCad
Researched some parts
Added TRRS jack for headphone output

Time spent: 7 hrs

2025-06-26 & 2025-06-29

(i went to Sydney for two days and forgot to journal but i came back and locked in) - Set up Windows LTSpice using Wine - Small changes to schematic - Routed PCB - Made case (its so cool that you can import an image, resize it, and trace it to model parts lol) - Changed some capacitor footprints to obey the laws of physics - Made BOM and selected components from LCSC - Made logo - Added silkscreen art - Rendered case