29038I am definitely going to have to start a SOL restoration blog...
- Jan 23, 2013So the unhacking continues....
It looks the resistor at R14 is missing, it's a 1.5k
and there is a 1.5k resistor attached to a via near u47 that appears to be hanging in mid air (there isn't a silk screen so I assume its a hack unless it was used to pull a signal down/up as per a fix that is broken)
Also it appears someone tied the serial port RTS signal to a 5v trace.
I haven't removed the board yet from the machine, so there might be more underneath. I just need to make more room for parts on my bench as I remove them (i.e. wood sides and stuff) so they don't get damaged. Since this is a long term project I can 't just use my soldering table as I will be starting my Scelbi soon...
From a power supply perspective the power supply puts out about 4.7 volts on the 5v when not plugged into the motherboard, but 3.7 volts when plugged in, so something is drawing it down. I removed and reseated all the chips and I just ordered a large sheet of antistatic foam so I can pull all the chips and perform the check out procedure from the manual for the video, then processor. Hopefully I can find it that way.
It would help if at some point I can play with someone else's Sol to see what I should see when there is no personality module or Ram and then what it looks like when I start to plug them in. Also it would be helpful to see if my personality module even works, it's a mm5204 kind so I can't easily reprogram it or test it. I guess I could throw Solos on my 8k bytesaver and use it for now at the same address the personality module should be at, but I don't know if that will mess me up.
Someone on the Altair forum is planning an mm5204 programmer so I may have to buy one if I can't get a 2708 personality module and I'm not paying $100 to that guy on ebay, it's overpriced and the card is missing a chunk (I guess someone's dog got hungry)
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