Sinclair ZX Spectrum Plus

Configuration

• Built: Start of 1985 (produced by Samsund in ROK)
• Mainboard: Issue 4S
• CPU: Z80A (date code 8614)
• ULA: 6C001E-7 (date code 8451, probably made in Philippines)
• RAM: 48KB (upper: OKI M3732L-20)

Trivia

• Got this from a bundle of two ZX Spectrum+.
• The previous owner added a power LED, a audio/monitor connector, and switches with an unknown function. He did it in a very professional and careful way. From the outside, these modifications look like they have always been there.
• There is one additional switch for color or black/white video, and another switch for internal or external audio.
• Has an additional red power LED as modification.

Known Issues

• The rainbow logo is worn out.
• Softener of the mod wires is melting the plastics and need renewal.
• External monitor connector is rusting.
• System seems to be recapped, the quality of the Samhwa brand caps needs to be checked.
• Additional filter caps at CPU and ROM. Should be removed for safety if tantalums.

History

• 2022-05-20: Date of purchase