Waiting for stock: This item will be restocked in aprox 2-3 weeks
512k ROM (1024kb) TI-99/4a cartridge PCB
The Red boards use a .1uF cap, not a 22pF cap. The 22pF works, but the .1uF is more stable. Note that these will also work with several types of nonvolatile SRAM chips, up to 512K as well. . .and up to 1MB (in the form of two 512K banking zones) if you add the SPST switch and 2.2K resistor on the left side of the board (do not install the resistor if you are just planning on using the board in 512K mode or less).