Portable ZX Spectrum

The venerable Sinclair Spectrum is from the 1980's and it was standard practice then to attach computers to a TV for the video output. This is inconvenient these days as TV's tend to be large and not the sort of thing you can cart about. So I had the idea for a 'portable-iser' which can be used to make a spectrum into a portable setup. Removing the need for a TV is pretty high up the list of things to do. I heard rumours on t'Internet of people using small LCD monitors with single board computers. They are designed for rear view cameras on cars. I ordered a couple, and then modified my spectrum to output composite video instead of modulated RF. This is just a matter of taking the input to the modulator in the Spectrum and connecting it to the RCA output connector (and disconnecting the RF signal to that connector). This gives a signal we can feed straight into the LCD monitor. The LCD requires 12V, apparently, it says so on the box. It turns out that you can use the 12V signal on the edge connector to drive the LCD.

The Spectrum was powered by a mains adapter, that's not very portable, so I wired a battery pack to the same connector the adapter uses and voila! We have a protable spectrum setup:

You can see the video on the LCD monitor works quite well, as the resolution is pretty low. It's colour too.

The only thing missing is some form of non-volatile storage, I tried a minidisc player but it didn't work for some reason I haven';t worked out yet. An SD card or MP3 player device would be good.
For now having a portable setup is good enough.