ATARI 520ST External PSU

Atari ST PSU by Electroware: a fresh, safe start for your Atari 520ST or 260ST — modern 50 W external replacement to power and preserve your classic.

Stay original! Choose genuine Electroware gear and beware of overrated clones flooding eBay & the web.

GET THE NEW PSU — YOUR ATARI 520ST, 520ST+ OR 260ST (YES, IT EXISTS!) DESERVES IT.

The original Atari 520ST/260ST shipped with a large, heavy external switching PSU (typical ratings around 5 V @ 3 A, 12 V @ 0.03 A, −12 V @ 0.03 A). After ~40 years, capacitor ageing and drift can cause instability or dangerous over-voltage spikes that threaten custom chips — especially when the old unit is overloaded.

Our Atari ST replacement PSU delivers 50 W (55 W peak) combined output — over 2× the headroom of typical originals — yet it’s about 2× smaller and weighs ~0.4 kg, saving space on your desk.

Many ST setups today include modern enhancements: SD/FDD emulators, CF/SSD HDDs, HDMI/VGA adapters, Wi-Fi modems, RAM upgrades and accelerators. These increase load and demand a clean, stable PSU. A stressed vintage supply becomes unpredictable.

Beware of “cheap replacements” that omit the −12 V rail (needed, e.g., for RS-232-C serial) or skip a proper main ON/OFF switch to cut costs. Our approach: meet the original three-rail spec with more current headroom, low ripple & noise and a robust mechanical rocker switch for safety and real energy saving (no pseudo-standby).

UNIQUE FEATURES & QUALITY: THE ABSOLUTE BASICS OF A MODERN ATARI 520ST (260ST) PSU

Standard Atari ST External PSU features:

• Compatibility: ATARI 520ST, 520ST+, 260ST, 260ST+
• Stabilized & filtered 5 V DC up to 4.0 A (4.4 A peak)
• Stabilized & filtered 12 V DC up to 2.0 A (2.2 A peak)
• Stabilized & filtered −12 V DC up to 0.5 A (0.55 A peak)
• Active & passive over-voltage protection on the main 5 V rail
• Over-current protection on all rails
• Fully isolated & AC-side fused input
• Reliable Power ON/OFF switch
• 1.8 m output cable with 7-pin round DIN (female)
• Detachable AC input cable (all versions)
• Weight ~0.4 kg (≈2× lighter than the original Atari ST PSU)
• Runs cool thanks to high-efficiency design
• Built on genuine Mean Well RPT-60B industrial/medical-grade module (low ripple & noise)

GO BEYOND THE BASICS: ADD THE ATARI ST ADJUST & PROTECT MODULE

NEW Adjust & Protect LED Module add-on — advanced power features:

• 5 V fine-tuning trimmer (approx. 4.9–5.3 V)
• Power-good LED (green)
• Redundant, fast over-voltage protection for the 5 V line
• Ultra-fast TVS for spike suppression
• Redundant, resettable over-current protection on 5 V
• Extra ripple reduction via low-ESR capacitor filtering

UNIQUE FEATURES & QUALITY

Choose genuine Electroware to get build quality and user-focused features clones typically miss:

• A reliable ON/OFF switch is a must for Atari ST PSUs
• Detachable AC input cable (we include a standard cable; longer cables can be used)
• High-quality 7-pin round DIN (female) — 100% Atari 520ST/260ST compatible
• Serviceable design — 100% repairable by qualified technicians; spare parts available
• Industrial wire-to-board connectors on all cables — no risky direct AC/DC wiring

Adjust & Protect module — advanced benefits:

• 5 V fine-tuning (approx. 4.9–5.3 V)
• Power-good LED (green)
• Fast, redundant over-voltage protection (5 V)
• Ultra-fast TVS spike suppression
• Redundant, resettable over-current protection (5 V)
• Additional ripple reduction via low-ESR filtering

TRUST & RESPONSIBILITY

Every Electroware PSU is triple-tested before dispatch. To ensure long-term reliability we test with original Atari hardware and run burn-in with up to ~150% overload (relative to a stock Atari 520ST/260ST) using custom load fixtures.

Stay with genuine Electroware products for build quality and community-proven features.

By choosing this product you support the retro-computing community and our continuous development. Thank you!

Warning!

Risk of electric shock and energy hazard when opened. Service by qualified personnel only. Protect ventilation from foreign objects and liquids. Do not install in high ambient temperature or near heat sources. Indoor use only; not for dusty or high-moisture environments. Do not exceed rated output current/power.

This replacement Atari ST PSU is designed exclusively for Atari 520ST and 260ST systems and should be considered part of the Atari ST setup. Do not connect to other devices; it is not a general-purpose PSU. A modern, correct PSU reduces failure risk but cannot guarantee full function of a ~40-year-old system.

Stay original! Choose genuine C64PSU.com gear and avoid clones on eBay & the web.