Eurorack 12V AC Power Inlet

Table of Contents

This module lets you safely and neatly bring 12V AC power into your modular case. It features a barrel jack connector, an on/off switch, and a power status LED, making it easy to manage your system’s power state at a glance.

Perfect companion for the Power Supply Unit.

Buy kit or PCBs in my store

Key Specs
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12V AC input
On/off toggle switch
Power status LED
5.6mm / 2.1mm barrel jack for AC input
2-pin screw terminal for connection to power supply
4 HP panel width

How It Works
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This module provides a simple way to route 12V AC from an external wall wart adapter into your case — no drilling or case modifications required.

Just plug in your AC adapter via the barrel jack connector, and the power is sent to your internal power supply through the 2-pin terminal. The LED indicator shows when the module is powered, and the switch allows quick control of the connection.

Build Guide
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Start with the small components: solder the resistor and diode to the component board.
Next, solder the capacitor and 2-pin terminal.
Mount the barrel jack connector to the front panel.
Assemble everything using the screws and spacers, and secure the switch nut.
Finally, solder the switch, LED, and both wires between the connector and the board.

💡 Tip: Since the module uses AC, polarity doesn’t matter — you can solder the two wires in either orientation.

See the Component Basics guide for help identifying parts.

BOM
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Reference	Value	Footprint	Qty	Description
C1	47u	Capacitor_THT:CP_Radial_D6.3mm_P2.50mm	1	Electrolytic
D1	LED	LED_THT:LED_D5.0mm	1	LED 5mm
D2	1N4148	Diode_THT:D_DO-35_SOD27_P7.62mm_Horizontal	1	100V 0.15A standard switching diode, DO-35
J1	AC IN	Connector_Wire:SolderWire-0.75sqmm_1x02_P7mm_D1.25mm_OD3.5mm	1	Connector for barrel jack
J2	AC OUT	TerminalBlock:TerminalBlock_bornier-2_P5.08mm	1	2-pin terminal connector
R1	1k	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	1	1/4W 1% resistor
SW1	SW_SPDT	POLYKIT:switch-spdt	1	Switch, single pole double throw

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Key Specs#

How It Works#

Build Guide#

BOM#

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Key Specs
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How It Works
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Build Guide
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BOM
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