2 layers64.8 × 100 mm Offset atten pcb, the printed circuit board in 3D

Offset atten pcb

A collection of free & open source DIY synthesizer module designs for Eurorack

Size: 64.8 × 100 mm
Copper layers: 2
Thickness: 1.6 mm
Parts: 50
Nets: 48
Pads: 164
Tracks, vias: 420, 3
Pours: 2
Routed: Yes
KiCad: KiCad 9.0 (file 20241229)
Created: 17 Dec 2019
Updated: 3 Nov 2026

Overview

Offset atten pcb is an open-source printed circuit board by QuinnFreedman, from the QuinnFreedman/modular repository on GitHub. It is a 2-layer board of 64.8 × 100 mm with 50 parts on 48 nets, routed with 420 tracks and 3 vias.

It is built around the LM324. Its parts include 16 resistors, 10 capacitors, 9 connectors, 2 ICs and 2 diodes. It belongs with the audio and music boards of this library.

Main components

LM324
SOP-14-1.5V~10V 0℃~+70℃ 24V 250nA 3V~20V 4 40mA 50nA 700uA 7mV 80dB SOP-14 Operational Amplifier ROHSHXY MOSFETOperational Amplifier

README

README.md

This project is an attempt to make Eurorack modular synthesis affordable and accessible to everyone.

This repository contains open source software and hardware schematics for Eurorack modules which are designed to be assembled easily and cheaply without any technical knowledge. Every module should be able to be assembled for around $20 in about an hour of work, even with limited experience.

To get started, check out some of the links below. Or get in touch! Send me a message at freemodular@gmail.com. Follow my reddit, Etsy shop, or GitHub.

Happy travels on your modular journey!

Go to the website to see more

Modules

{% include_relative docs/modules.md %}

Parts

Qty	Value	Footprint	References
9	100k	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R5, R6, R7, R8, R9, R11, R12, R13, R14
4	100nF	Capacitor_THT:C_Disc_D4.7mm_W2.5mm_P5.00mm	C3, C4, C5, C6
4	33k	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R1, R2, R3, R4
4	33pF	Capacitor_THT:C_Disc_D4.7mm_W2.5mm_P5.00mm	C7, C8, C9, C10
4	B50k	FreeModular:Alpha_Potentiometer_Grounded	RV1, RV2, RV3, RV4
4	M3x11mm	MountingHole:MountingHole_3.2mm_M3	H1, H2, H3, H4
4	THONKICONN	FreeModular:THONKICONN_perf	J1, J2, J3, J4
2	10uF	Capacitor_THT:CP_Radial_D4.0mm_P1.50mm	C1, C2
2	1k	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R10, R15
2	3mm	LED_THT:LED_D3.0mm_Clear	D1, D2
2	Board	kikit:Board	B1, B2
2	LM324	Package_DIP:DIP-14_W7.62mm	U1, U2
1	10k	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R16
1	Conn_01x07_Pin	Connector_PinSocket_2.54mm:PinSocket_1x07_P2.54mm_Vertical	J7
1	Conn_01x07_Socket	Connector_PinSocket_2.54mm:PinSocket_1x07_P2.54mm_Vertical	J8
1	Conn_01x10_Pin	Connector_PinSocket_2.54mm:PinSocket_1x10_P2.54mm_Vertical	J5
1	Conn_01x10_Socket	Connector_PinSocket_2.54mm:PinSocket_1x10_P2.54mm_Vertical	J6
1	Eurorack_2x5_Power	Connector_IDC:IDC-Header_2x05_P2.54mm_Vertical	J9
1	logo_small	FreeModular:logo_small	G1

Questions

How big is the Offset atten pcb PCB?

It measures 64.8 × 100 mm and has 2 copper layers, 1.6 mm thick.

What parts does the Offset atten pcb use?

50 parts, built around the LM324. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.

Where can I download the Offset atten pcb KiCad files?

From the QuinnFreedman/modular repository on GitHub, at the commit this page was made from: the board is modules/OffsetAtten/PCBs/offset_atten_pcb/offset_atten_pcb.kicad_pcb. PCBKit opens the board in the browser, with nothing to install.

Can I use the Offset atten pcb design in my own project?

Its repository states no licence, so its author keeps all rights: ask QuinnFreedman before reusing the design.

Category and platform

Audio and music

Topics

eurorack music modular

Project files

Show this board on your page

A live frame, for any web page

<iframe src="https://pcbkit.io/embed/boards/quinnfreedman-modular-offset-atten-pcb" title="Offset atten pcb in PCBKit" width="100%" height="480" style="border:0;border-radius:12px" allow="fullscreen" loading="lazy"></iframe>

A picture

<img src="https://pcbkit.io/embed/boards/quinnfreedman-modular-offset-atten-pcb.jpg" alt="Offset atten pcb" width="1200" height="900">

A picture that opens the board, for a README

[![Offset atten pcb](https://pcbkit.io/embed/boards/quinnfreedman-modular-offset-atten-pcb.jpg?size=s)](https://pcbkit.io/boards/quinnfreedman-modular-offset-atten-pcb)

Source

Repository: QuinnFreedman/modular
Board file: modules/OffsetAtten/PCBs/offset_atten_pcb/offset_atten_pcb.kicad_pcb
Commit: c78d208
Homepage: freemodular.org
Licence: Not stated

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