We got 2 of those to boot, of which one with malfunctioning keyboard and the other with a horrible RF picture, far worse than the other Speccys that only displayed static garbage using the same antenna cable and TV. Thus within that group, the power supplies tend to be fairly swappable.Īlso, a friend of mine yesterday brought out 8 various ZX Spectrum 16/48K from his collection. Voltage is harder to determine based on trace thickness.įor reference, the ZX Spectrum, Nintendo Famicom (*), Sega Master System, Genesis/Mega Drive and a few more consoles (NEC PC Engine I believe, but don't quote me on that) all take centre negative polarity, about 9-10V DC and approximately the same number of ampere. I always double-check on the machine, Internet and if it can't be determined, by opening it up and check traces on the motherboard to identify polarity. 680 one way between collector and base and a reading of.
The 213 reads nothing between collector and emitter both ways, a reading of. 057 between collector and base both ways (that MUST mean it's blown) and nothing both ways between base and emitter on the 650. In diode check mode my DMM reads nothing between collector and emitter both ways, a reading between of. Best I can be told is that either the ZTX650 or the ZTX213 has also blown but I can't determine from testing if they are healthy or not, or if my problem is something completely different. I can't even get straight answers on where good voltage test points are. Unlike Commodores where there's piles of documentation on how to troubleshoot everything there's almost nothing I can find for the Spectrum.
I replaced that and switched the polarity on my AC adapter and now while the new 7805 has a healthy +5 out all I get is a white screen. So after careful selection of a power supply (I found one rated for 10v 3a which was the closest to the original 9v 1.2A I could get) I thought I was all set but no, Sinclair decided it was a great idea to reverse the pins on the DC jack and not include a protection diode so after several cautious seconds watching my display to show something there was a pop and the 7805 blew.
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