Jules Richardson wrote: Well the guy who collected the $10K for the "Moore's Law" article kept his excess under the floorboards ... I assume you've already aexhausted that avenue? Antonio -- --------------- Antonio Carlini arcarlini at iee.org

One time when I powered up my Model 4, I got the unmistakable smell of burning tantalum capacitor, and magic smoke came out. The darn thing continued to boot and has worked fine ever since. I assume a decoupling tant decided to go short-circuit, but I've not got round to pulling the case to check. -tony

Not unless you know what you are doing, and more importantly know you could put right any problems caused by said exploded capacitor. I do know the Model 3 and 4 pretty well (even if I say so myself), I've done component level repair on them, etc. I have all the schematics (including my only reverse-enginnered schematic of the PSU board, which is a lot more accurate than the one in the technical manual, which it seems was also reverse-engineered (based on the lack of identification of some components, lack of transformer winding details, etc)). In other words, if there are subsequent problems, I know what to do. A tantalum bead that exploded like this one did pretty much has to be a supply decoupling capacitor. In any other position, it would be able to pass enough current to blow up like that. Well, maybe if it was on the primary side of the SMPSU, but (a) if one of those shorted most likely that PSU would stop working and (b) from what I remmeber there are no tants on the PSU boards. As the machine continued to boot, it was a fair bet that the capacitor was not shorting out any of the supply lines. It had burnt itself out. By the time I could have turned off the power it would most likely have done that. In which case there's little harm in running the machine with one capacitor effectively missing. -tony

It wasn't the cassette interface that was the problem, it was the cassette recorder that was shipped with the machine (or at least the type that was shipped with my first Model 1). This recorder had the amazing trick of putting glitches on the tape if started or stopped using the remote control socket, even in playback mode (!). Needless to say that was great for ruining tapes! The cure was either to use a properly desigend recorder, or to solder a 10uF capacitor (the right way round) across the erase head (this infernal device used DC erase, BTW). After doing that, I had no problesm with the cassette interface apart got the EI and disks. My M3 and M4 I bought second-hand, complete with internal drives. -tony