ATARI 520ST & SF314 PSU "2in1"

Atari ST “2-in-1” PSU by Electroware — a fresh start for your Atari 520ST or 260ST with SF314/SF354 floppy drive.

Efficient, medical-grade 55 W supply built to protect and preserve classic hardware. It replaces two bulky originals, saves desk space, and delivers peace of mind. The optional “Adjust & Protect” module adds 5 V fine-tuning, extra ripple filtering and layered protections.

Stay original! Choose genuine Electroware gear — beware look-alike clones on eBay & the web.

ATARI PSU “2-in-1”: SAVE DESK SPACE & ENERGY. REPLACE YOUR ATARI 520ST & SF314 BRICKS WITH ONE MODERN PSU.

Atari 520ST (and 260ST) systems originally shipped with large external switch-mode PSUs. The ~17 W computer brick provided 5 V DC@3 A, 12 V DC@0.03 A and −12 V DC@0.03 A. The popular external FDD used a separate ~7 W unit (5 V DC@0.72 A, 12 V DC@0.21 A). After almost 40 years, electrolytic capacitors dry out and tolerances drift, which can cause ripple and dangerous voltage spikes — especially under overload or with drives that have increased mechanical friction.

If your original PSU is weak, unstable or simply unknown, it’s time for a solid “2-in-1” replacement. Our unit delivers a combined 50 W (55 W peak) — comfortably more than the two originals together — yet it’s around three times smaller and lighter (approx. 0.4 kg), keeping your workspace clean and your hardware safe.

Many ST setups today include modern add-ons: FDD emulators (SD), CompactFlash hard drives, video enhancers, VGA/HDMI adapters, Wi-Fi modems, RAM upgrades and accelerators. These extras raise current demand. A robust, low-ripple PSU is essential for stability and component longevity.

Note: cheap replacements often omit the −12 V rail (used by the RS-232 serial port) or skip a proper mains power switch to cut costs. Our approach is the opposite: all three voltages per Atari specification, with higher current headroom, plus a reliable mechanical ON/OFF rocker for safe start-up, true zero-standby power when off, and better overall safety.

UNIQUE FEATURES & QUALITY: THE ABSOLUTE BASICS OF MODERN ATARI 520ST (260ST) & SF314 / SF354 FDD POWER SUPPLY

Standard Atari ST “2-in-1” PSU features:

• ATARI 520ST, 520ST+, 260ST, 260ST+ compatible (main output)
• ATARI SF314, SF354 compatible (secondary output)
• 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 +5 V line
• Over-current protection on all outputs
• Fully isolated and fused on the AC side
• Power ON/OFF rocker switch
• Long 1.8 m computer cable with round DIN 7-pin female plug
• Detachable FDD power lead (disconnect when not in use)
• Detachable AC input cable on all versions
• Approx. 0.4 kg total weight (about 3× less than the original pair)
• Runs cool in comparison to the original bricks
• Safety standards: UL60950-1, TÜV EN60950-1, ANSI/AAMI ES60601-1, TÜV EN60601-1, IEC60601-1

GO BEYOND THE BASICS: ADD THE ATARI 520ST “2-in-1” PSU EXTENSION MODULE

NEW Protection & Adjustment LED Module add-on — advanced functions:

• 5 V fine-tuning trimmer, 4.9–5.3 V range (shared by computer & FDD outputs)
• “Power-good” status LED (green)
• Redundant, fast over-voltage protection for 5 V line
• Voltage spike suppression using ultra-fast TVS diode
• Redundant, resettable over-current protection for 5 V line
• Additional ripple reduction with low-ESR capacitor filtering

UNIQUE FEATURES & QUALITY

Choose original Electroware products to get top build quality and features you won’t find in generic clones:

• A dependable mechanical ON/OFF switch is essential for the Atari ST
• True “2-in-1” capability: powers popular ATARI SF314/SF354 floppy drives
• Detachable FDD power cable for convenience
• Detachable AC input cable (use longer leads when needed)
• High-quality round 7-pin female plug — 100% ATARI 520ST/260ST compatible
• Serviceable design: fully repairable by qualified technicians; spare parts available
• All internal cables use industrial, detachable wire-to-board connectors — no unsafe direct soldered mains or DC leads

Protection LED Module — advanced functions:

• 5 V fine-tuning 4.9–5.3 V
• Power-good LED (green)
• Fast redundant over-voltage protection (5 V)
• Ultra-fast TVS spike suppression
• Resettable redundant over-current protection (5 V)
• Extra ripple suppression with low-ESR capacitors

TRUST & RESPONSIBILITY

Every Electroware PSU is triple-tested before dispatch. We verify on original Atari hardware from our collection and perform burn-in with custom loads up to 150% of a typical 520ST/260ST system with SF314 — to ensure stable performance and long life.

Choose original Electroware products for proven build quality and unique features unavailable in generic copies.

By purchasing this product, you support the retro community and our ongoing development. Thank you!

Warning!

Risk of electric shock and energy hazard when opened. Service only by qualified technicians. Keep ventilation openings free from foreign objects and liquids. Do not install power supplies in high ambient temperatures or near heat sources. Enclosed power supplies are intended for indoor use only; do not use outdoors, in dust or high moisture. Output current and wattage must not exceed rated values.

This replacement Atari ST PSU is designed for Atari 520ST & 260ST systems using ATARI SF314/SF354 FDDs and should be treated as a component of the Atari ST system. Do not connect it to other devices; it is not a general-purpose PSU. The manufacturer is not responsible for consequences of unauthorized repairs, modifications or incorrect use. A new, properly working PSU reduces failure risk but cannot guarantee full functionality of a ~40-year-old system.

Stay original! Buy only genuine C64PSU.com gear and beware of overrated clones flooding eBay & the web!