Just happened to take a closer look at the PSU of my 1541-II disk drive (PSU type number: DV-5128UP), and it says on the case, that the transformer outputs 5V DC and 12 V DC. What do you think - could this unit be used for powering the MBSID? Of course, a new optimized power circuit would have to be designed, but how about it? The voltages would be just right for a Core and SID 6581.
Not that this matters to me personally, as I use my C64 PSU with the optimized circuit, but this might actually help somebody out there.
I also have one of these powersupplies, and I just realized it after already building the optimized power circuit for the standard C64 power supply (not a big deal, anyways..)
Can I just plug this right in? the Pinout is +5v/+12v/GND (other pin is NC). I’m using a 6581 and currently my SID board has a 12v regulator in it, which I’m assuming would end up doing nothing (but is it okay to leave it there?)
The reason I ask is that someone said:
“Of course, a new optimized power circuit would have to be designed, but how about it?”
Is this necessary?
Cheers,
Tom
Edit: The readings from the PSU are giving me: 12.08 for the 12v DC, 5.58 for the 5v DC. Is 5.58 too hot?
if the PSU you’re using already has regulators on board for 5V and 12V I wouldn’t stuff te regulators on the boards (unless you’re using 8580 SIDs, then you should stuff 7509 or 75L09 on the SID boards). The 5,58V is fine for the Core, 12,08 is also fine for the 6581 SID, or to feed into the 7809/78L09.
The following text is a statement of which I do not know if it is 100% correct, read my topic on the Midibox PSU for details and/or a reply from someone who can confirm the statement.
Remember that if your PSU is not regulated, the voltages you measure now could be up to 20% higher if you plug in the PSU at an other location! In that case, it might be wise to DO stuff the regultaors on the Core and the SID, even if you use the 6581.
Sure, I can do that, I’ll poke around for the best place to do so.
Edit: Actually, I should investigate it’s usage a bit more first, see if anyone has any suggestions and make sure it _is_ an appropriate power supply.
My 6581 SID operates pretty weird. It often does things such as, OSC’s randomly drop out of notes, filtering seems to be very inaccurate (doesn’t really do what it should in any mode, sometimes it does but doesn’t always), etc. OSC’s sometimes play the wrong frequency (and hitting the note a second time, the OSC will play the right frequency). Basically every time I play a note there’s a certain percentage of the sound that is random. If I apply the filter to all the oscillators, then often the sound simply cuts itself off.
Does this sound like problems induced by a bad power supply? (keeping in mind that I *did* potentially roll over my SID chip with a chair, so I could just have a half-busted SID at this point )
FWIW, I love it anyways, it’s unpredictable-ness makes for a far more entertaining synth than anything I could buy.
(not a big deal, anyways..)
)