Sinclair ZX Spectrum+ upgrades

Replaces the Z80 and upper 32 KB of DRAM in a ZX Spectrum 48K, Spectrum+, or Timex TC 2048 while adding AY sound.

For this system (exact model): The seller explicitly names ZX 48+. Confirm motherboard layout and clearance before removing the CPU and disabling the original upper RAM.

The seller exposed a login-or-register-to-buy path for MAMLAS on 2026-07-27; its Z80SRAM predecessor is discontinued. MAMLAS installation is invasive: remove the original CPU and any socket, disable or remove the upper 32 KB DRAM, and solder the module directly at the CPU footprint with correct pin-1 orientation. The audio connector is not included, and a ZX Spectrum 48K heat sink may need to be bent for clearance. Do not install the module on top of its shipping or protective bottom socket. Used Z80SRAM boards should be treated as a distinct earlier revision and checked against their archived instructions.

Adds a PS/2 or PS/2-compatible USB keyboard to a ZX Spectrum 48K or Spectrum+ through an internal keyboard-interface board.

For this system (exact model): The seller explicitly names the ZX Spectrum 48+. Confirm the motherboard's keyboard-read signal mode before choosing the zero-ohm jumper setting.

The seller exposed a login-or-register-to-buy path on 2026-07-27. It explicitly targets the 48K and Spectrum+ and warns that the original keyboard may stop working while the adapter is installed. The two signal modes use different motherboard signals; select the documented jumper state for the exact board and change hardware only with power removed. A USB keyboard works only if it supports the PS/2 protocol through its connector.

Replaces the ULA, video RAM, upper RAM, and RF modulator in Issue 2 through 6 ZX Spectrum 48K boards while adding modern video, sound, memory, and machine modes.

For this system (exact model): The seller's announcement explicitly includes the ZX 48+, subject to the same Issue 2 through 6 motherboard requirement and invasive installation as the original 48K case.

The seller listed availability after 2026-08-31 and exposed a preorder path on 2026-07-27. Installation is invasive: remove the ULA and RF modulator, disable or remove the original DRAM, connect M1, RESET, IORQ, and RFSH at the Z80, and install the supplied RGB adapter and ribbon cable. The output is digital RGB only, not composite or YUV. Verify board issue, pin 1, wiring, case clearance, display compatibility, and the current installation guide before work.