Description
Crystal Clear Visuals: The Definitive ZX Spectrum Jailbar Fix
The “Jailbar” Problem:
Many Sinclair ZX Spectrum computers—particularly the later issue motherboards—suffer from vertical “jailbars” visible on the screen. These faint vertical stripes are especially prominent on solid-coloured backgrounds and can be intensified when using modern LCD or LED televisions. This interference is typically caused by noise on the power lines feeding the video RAM and ULA.
The Solution:
This kit provides a set of four 220nF ceramic disc capacitors, which are the community-standard value for the popular “Jailbar Mod.” By installing these components in positions C5, C6, C7, and C8 on your Spectrum motherboard, you provide better decoupling for the memory chips, filtering out the electrical noise that manifests as vertical lines in your video signal.
Key Features:
- Targeted interference Reduction: Specifically designed to tackle the common vertical line issue on Spectrum 48k models.
- Complete Set: Includes all four capacitors required for the standard C5–C8 modification.
- High Quality: Stable 220nF ceramic disc capacitors suited for long-term reliability in vintage electronics.
- Standard Footprint: Compact Disc design for easy soldering even in the relatively crowded internal layout of a Sinclair machine.
Compatibility:
While primarily used for the 16k and 48k “Rubber Key” and “Plus” models, this mod is a staple for any Spectrum motherboard showing visual interference. Note that this modification requires basic soldering skills.
