Apple IIe Aftermarket PSU (Delta Electronics)

For more information, see this article's corresponding Wikipedia page: Device.

Delta Electronics Apple IIe power supply (external)

This is the page for the Delta Electronics MW 302 AP aftermarket power supply for the Apple IIe

Power supply should normally output voltages specified on outer casing (+/-5VDC and +/-12VDC) in an unloaded condition.

Known Issues

Non functional / clicking when powered on

NOTE: Many Apple IIe power supplies (Astec branded) "click" when powered on if they're disconnected from the motherboard and will not provide proper output voltages when unloaded. Some, however, provide constant output regardless. Limited experience with aftermarket PSU's suggest a constant output is to be expected.

Causes

• Blown / failed electrolytic capacitors

Solutions

• Replace electrolytic capacitors

Disassembly Notes

Seven screws to disassemble case. Will need to remove power switch from end to remove board from enclosure.

Desolder Line, Neutral, and Ground wires from NEMA plug connection to separate board from case completely.

Original Parts

Power Supply PCB

Underside stamped with "MW 302 AP". "Delta Electronics" name found on back of NEMA plug.

Table Notes

• Capactiances are in microfarads (µF) unless otherwise noted
• Dimensions are in millimeters (mm)
• Temperatures are in degrees Celsius (°C)

Capacitor Specifications and Footprint Information

RefDes	Qty	Capacitance	Voltage	Diameter/Size	Height	Lead Spacing	Temp	Type	Brand
C!	1	0.1	250VAC	17.8	12.5	15.6	0	Film (PP) - X2	ISKRA
C2, C3	2	4700 pF	250VAC	13	11	10.5	0	Film (PP) - Y	ISKRA
C4, C5	2	100	200	16.2	33	7.8	85	Electrolytic	Jamicon
C6	1	100	25	6.6	11.6	3.4	85	Electrolytic	N/A
C7, C8, C12	3	10	63	5.2	11.2	2.9	85	Electrolyitic	N/A
C13, C14, C15, C16, C17	5	1000	16	13	25.8	5.8	105	Electrolytic	N/A
C18, C20, C21	3	220	16	8.3	12	3.5	85	Electrolytic	N/A
C19	1	470	16	10	15	5.4	105	Electrolytic	N/A

Replacement Parts

Power Supply PCB

Replace original parts in kind. See Digikey BOM in Kits section for an example list.

Recommendations

• Maintain lead spacing
• Maintain / reduce diameter
• Prefer 105 °C or greater temperature ratings.
• Prefer low ESR caps for DC voltage output (C16, C17, C20, C21)

Basic PCB Name

Capacitors

RefDes	Qty	Compatible Part Number	Order Links
C!	1	890324025017CS	DigiKey Mouser
C2, C3	2	CMPPAC310V472K10S5	DigiKey
C4, C5	2	EKXJ251ELL101ML20S	DigiKey Mouser
C6	1	25ZL100MEFCT16.3X11	DigiKey Mouser
C7, C8, C12	3	ECA-1JHG100I	DigiKey Mouser
C13, C14, C15, C16, C17	5	16YXJ1000MT810X16	DigiKey Mouser
C18, C20, C21	3	860010373010	DigiKey Mouser
C19	1	16YXF470MEFCT810X12.5	DigiKey Mouser

Kits

• Digikey BOM: https://www.digikey.com/short/22pwn3bz

Related Links

• YouTube - Chris Torrence Assembly Lines #44: Apple II PSU Testing