arumblack Posted February 7, 2004 Report Share Posted February 7, 2004 hey all, i just threw together a sid module and when i do the voltage test i get 13.7 or so volts. i find this odd because, 1) i should get 12, and 2 i am only using a 12 volt ac supply? i am guessing this is not ok(nearly 2 volts higher than it should be.) i don't want to fry my sid... i have checked for solder bridges, i don't see any and i poked around with a continuity tester in suspect area's.the only thing that i think it could be, is that i left out the 1nf cap on the audio input,because i must have forgot to order it. i was hoping this wouldn't be a problem, i don't need the audio input right now, but i shure would love to hear some sid....any idea's? or will this 13.7 volts be ok? the 7812 gets warm, but that is normal right? although i havent left it on too long, maybe it gets hotter?any help apreciated. Quote Link to comment Share on other sites More sharing options...
Phattline Posted February 7, 2004 Report Share Posted February 7, 2004 After the7812 you should get 12 VMaby idle Voltage (german:leerlaufspannung)What PSU do you have? Quote Link to comment Share on other sites More sharing options...
arumblack Posted February 7, 2004 Author Report Share Posted February 7, 2004 a wall wart, 12vac,830mAafter the 7812 i get the same,13.7 or so volts. the measurement stright from the wall wart, with nothing plugged in is about 15v. Quote Link to comment Share on other sites More sharing options...
Phattline Posted February 7, 2004 Report Share Posted February 7, 2004 Take a second meaning, i dont know if i´m right but: the 7812 gets hot? there is no big consumer after the 7812 hmm´.... by a short the voltage should fall (depends from the vA of the psu)....On the other IC´s the 5 V are here? (Pin 16-8) or also more then 5 v The Sid take´s not much A (under 100mA I read)I dont think that the Voltage fall to 12V when the SId is plugged in.(but I´m not sure)The 1nF?-I dont believe? Check your circuit again:Test your Transistors (also the placement->rotation)Sorry If I tell you things that you already know Quote Link to comment Share on other sites More sharing options...
arumblack Posted February 7, 2004 Author Report Share Posted February 7, 2004 The other ic's get 5v from the core, which isn't wired up yet. (or am i wrong here? i checked and they were not getting 5v.)perhaps the 7812 is bad? i am by far no expert, but how otherwise could i get nearly 14 volts from it?the sid page says i should get 12v without the sid plugged.i will check the transistors, but they should be placed right,the layout is the one published here and the part is bc547a. this still wouldn't make it 13.7 volts directly after the 7812 though would it? Quote Link to comment Share on other sites More sharing options...
arumblack Posted February 7, 2004 Author Report Share Posted February 7, 2004 i am using a home made board, that i wasn't going to use after the core i made on a homemade board didn't work.i have since built a core from smash's boards and it works fine.maybe the board is bad? but it is by far the best one i made. perhaps i just have to wait and order new boards(like i was going to, but had a day off due to weather so i decided to try this board anyway). Quote Link to comment Share on other sites More sharing options...
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