My first three core modules

[nitro2k01]

Hello! This'll be my first post around here. Me and my friend Vektor have decided to join the madness and build some MIDIbox modules. I just etched three core module PCB's and I've started to solder components to them.

Why three? Well, when etching the two first, there were holes in some copper lanes, but third was ok. But I decided to fix these holes with a little solder, and drill the holes anyway. And then I just couldn't resist using all three of them.

A few comments: Mr Klose recommends that you connect the infamous R12 (The one below the 40-pin socket) early. This seems fair. But because I made a mistake when soldering that component, so I had a choice between removing the 40-pin socket or try to solve the situation anyway. I chose the latter of course. And using he right tools it was pretty damned simple to get it right. In fact I think it's better to insert R12 after the socket, because then you don't have to worry about the resistor being in the way of the socket.

Also I didn't have any 1k resistors (I keep on running out of these suckers!) so I wonder if it's best to replace it with an 820 Ohm or a 1.2 kOhm resistor. I know it's just there to pull up the voltage when nothing is connected, so intuitively, it shouldn't matter much with +/-10% difference. But still, what's the official recommendation? ;)

Another thing was the big electrolytic cap after the rectifier. I couldn't find any 2200 uF. (In the lab where I did this) The biggest I could find were 2*1000 uF and 1*820 uF. When feeding the thing with DC it seems far out to use even a 2200 uF cap, but even when feeding it with AC, 2200 seems pretty big. Do you really, really need such a big cap, or did you just choose some random big value?

Another thing, does the PIC chip support ICSP? If so, does the core schematic have conenctors for it too?

Yet another thing: Maybe it could be an idea for the next release, to include a place for a power indication LED? Personally, I'll fix that myself on my PCB's. (By cutting out a small cupper island so I have +5 V -> LED -> island -> resistor -> Gnd)

Anyway, big thanks for such a great project!