jdutcher Posted October 20, 2004 Report Share Posted October 20, 2004 hey, so i rebuilt my sid synth from scratch and i'm using the original c64 psu (6581 sid). the diagram (http://www.ucapps.de/mbhp/mbhp_sid_c64_psu.pdf) says that pin 1 of AC1 should be 9VAC but i'm getting 12V AC. could this be why it isn't working? also, is there any way to test the voltages coming out of AC2 and pin 2 of AC1? right now they read 7VDC (zero VAC), but i know that's wrong. i am getting 5VDC going to the diode, however, so that's working at least. the 470uf cap i'm using is from the original c64 circuit so it's 25V instead of 50V, but that shouldn't matter, right?thanksjames Quote Link to comment Share on other sites More sharing options...
pay_c Posted October 22, 2004 Report Share Posted October 22, 2004 Everything right (the cap and stuff) but only one thing: *Every* PSU has much more voltage if there is no current going out. So the 12V instead of 9V is OK. Give it a little current (like at least 50 mA) and you will see it dropping. Anyhow that should be no problem, because the 78xx is getting the voltage down to the needed level.Greetz! Quote Link to comment Share on other sites More sharing options...
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