A couple of years ago I've obtained (for not much money) this guy - Soviet clone of 48k ZX Spectrum. Unfortunately, it doesn't work (usual case, heh). So now it's time to resurrect and try to do something with it (maybe games, maybe even some assembly coding if I make UV EPROM programmer).
When I've bought this thing, I had a thought: "Hey, this could even work the first time!" Of course, that was not the case. Opening the case has shown nothing interesting (even no leaked electrolytes!), but first things first - I needed to connect it to power supply. Unfortunately, neither I had a TV or anything else to check RGB output nor the computer had a buzzer to produce sounds (which got me time to find out, heh). So the project was shelved for the first time.
Fast-forward some amount of time: I've acquried small analog input display (like 7" or so) and found a schematic for machine. So I cobbled together an 5-pin-to-RCA-jack adapter for video and tried connecting everything together. Image appears! But, for the second time, it does not behave properly - no sense can be made of it (just random color squares on the screen). So I decided to replace video driver IC (which also handles everything else including keyboard and sound).
It failed with the same symptoms. Then there was ROM, something 27C16-compatible. Desoldering and dumping it gave possible culprit - ROM was empty. How (it's factory masked truly read-only memory)? I don't know. Unfortunately, while this particular ROM can be bought on a second-hand markets, I couldn't obtain one.
And so we're left with a board without ROM in unknown state. Time to go on!