(DIY) Amiga 500Plus 1024KB Chip RAM Upgrade Board. 

Hello,

This is a tested and working project.

This A500+ Trapdoor Expansion is an Easy DIY project, all components are through hole, marked on the PCB, Easy to solder, Easy to make ;)

With this board you can Add 1MB chip ram to your Amiga 500 Plus

 Components:

8pcs. 256K x 4Bit dynamic DIP20 RAMs

8pcs. DIP20 IC sockets (some chips may be defective, sockets make easy to repace them)

15pcs. 68 ohm 1/4 wattt resistances

8pcs. 330nf 50V 5.08mm pitch (0.2inch pitch) ceramic capacitors

1 piece 2x28 pin female header. (get 2x40 pin female header then cut it)

(optional) 1 piece toggle switch (only for A500 (not plus) models, to switch On/Off 0.5MB slow RAM)

Some of compatible 256K x 4Bit dynamic RAMs list: (You can find from Aliexpress)

MB81C4256 (Fujitsu)

GM71C4256 (Goldstar)

HM514256 (Hitachi)

HY534256 (Hyundai)

MT4C4256 (Micron)

M5M44256 (Mitsubishi)

MCM514256 (Motorola)

MSM514256 (Oki)

KM44C256 (Samsung)

TMS44C256 (Texas Instruments)

TC514256 (Toshiba)

LC324256 (SANYO)

UPD424256 (NEC)

In order to protect your electronical devices, always turn off your Amiga before connecting or unconnecting any device.

Gerber files can be changed at any time. Before paying for the PCBs, be sure to update your orders!

Have fun

Thank you