There's a lot going on in this thread right now, and I don't really have time to get into a ton of detail, but I'll try to clear up a few things.
Mad_Hatter wrote:It can get warm even when the console is turned off.
This is normal. Current is always flowing through the primary of a transformer, when it's plugged in. The secondary doesn't conduct until you hit the power on the console. The coils on transformers are just tightly packed bundles of wound wire, and dipoles in the ferrite cores will still shift back and forth with only the primary conducting. Those things result in losses, which generates heat.
marurun wrote:I don't understand why the various components require their own power supplies. When you attach a PC Engine to a CD or Super CD unit, or a TG-16 to the Turbo CD, you use the power adapter for the CD unit for both, as the console draws power from the CD attachment. But you keep your original power adapter around for funsies, because if you want to detach the CD drive to use as a compact (but not portable) CD player, that's the power adapter you'll want to use.
I'm hazarding a guess here, because I don't know the exact reasons for the design decisions, but aside from not having the passthrough connection for the rail voltage at that connector, I'd imagine the PCE/TG16 requires significantly less current to power. One consideration for power delivery is the charge storage elements (capacitors). Especially with DC regulation, where one is trying to keep the voltage near a particular value. In reality, the actual DC voltage falls from the nominal value, the timing of which is based on the time constant: Resistance times capacitance. So the time constant can be increased, and the rate of decay can be slowed by increases capacitance, but this really has more to do with electric charge, and how much charge is required for all of the mosfets to optimally reach their gate threshold voltages. At any rate, if you want more charge, in practice, you often need a bigger (in physical size) capacitor, which comes with a mountain of headaches if you're already space limited.
Ziggy587 wrote:I can understand replacing the electrolytic capacitor, but is replacing the diodes really necessary? I mean, I know it's a part that can be had for like 10 cents a piece, but still.
I didn't look at it in great detail, but I noticed he mentioned cleaning up the power signal for better RGB. Diodes, SCRs, DIAC/TRIACs, etc, are inherently very noisy devices under certain conditions. Zener diodes are often used as ideal noise sources, for instance, when held near their reverse breakdown voltages. Diodes from the 80s were probably worse about their emitted noise. He replaces the ferrite cores also, for probably a similar reason. I would call those unnecessary replacements, but if the object is to clean up noise, it shouldn't hurt, at least.
