2019-04-01

Parcel of goodies arrived including MV1815 and SDA5273 chips. I removed the dead chips and fitted a new MV1815 and 64K x 4-bit DRAM chip. The phono socket used to be the UHF output from the tuner. As the analogue tuner was dead and obsolete, it has been removed. The phono socket can now be the video input to the teletext chip. The MV1815 outputs are red, green and blue, and will be routed to the RGB input pins of a SCART socket. This project will require a SCART-socketed colour TV, which I have.

I gave some chips to a workmate to play with. They might be useful as text overlay chips, but all the monitors at work are baseband monochrome. A few colour LCD monitors have SCART inputs. But there are obsolete analogue colour TVs available cheaply on eBay - collection only, they are too heavy to post.

2024-05-27 I had bought some SAA5281 chips in DIP48 recently, but rummaging in my many junk boxes I found a board with this chip in DIP52. It was salvaged from an old PC-TV receiver board. This saves me having to find and attach the handful of passive components. However, the connectors only carry power and I2C signals, and nor RGB outputs. The PCB has unpopulated footprints for components which I think must have been for buffering the RGB and blanking signals, but I do not know what they were. I shall wire those signals to the header pins and design my own circuit to buffer them up for SCART output.