This is a daughter board that allows you to use an unused AIIE 80COL card as a 64K RAM card, and can be installed in the AIIE 80COL card's IC socket.
RAM Hijacker type
DIY kit /13USD
*Kit includes all parts except DRAM x2.
Bare PCB /7USD*Parts other than PCB are not included.
Color: Black●, Purple●
Note: "Bare PCB" can be sent to you by international registered mail as a card item(up to 2 pcs due to weight limit).
Click here for this project details.
All you have to do is create a daughter card and add a jumper cable to change it to a RAM card!
Kit includes:
Quantity, Part locations, Part model number
2 R1, R2 Carbon resistor 100ohms 1/4W
1 R3 Carbon resistor 470ohms 1/4W
1 D1 M3 LED *I used Blue
2 C1, C2 Multilayer ceramic capacitor 0.1uF (100nF)
2 U1, U2 IC socket 18-pin
1set UA1, UB1, UC1 Round pin headers
*As shown in the picture, they are connected and can be folded and used, you will have a little left over
1 80COL card edge Jumper cable 1”(25mm)
*Other things you need are two 64Kx4 RAM chips and an 80COL card.
Download instructions here.
64Kx4 RAM chips are relatively easy to obtain. According to my research, if you search for "Texas Instruments TMS4464" on eBay, you can purchase it at the lowest price for 2 pcs/ 2 USD and shipping fee/3 USD(*As of March 10, 2024). You may also be able to purchase it locally.
The reason why these two chips are not included in the kit is because we had a bitter experience in which when we sent DRAM chips from Japan to the United States, the chips died due to X-Ray. We can't talk about the damage X-RAY causes to DRAM here, but if you google it you'll find a lot of literature. We have no idea how often these used DRAM chips fail. The salvaged DRAM chips sent from China had no failures(!). Maybe they don't have X-RAY used. These RAM chips can fail unexpectedly, so if you send two chips and even one fails, the kit is ruined. We also don't want to take any risks, so we decided not to include it in our kit. Please purchase it separately.