I agree Vince - the alignment is the killer in this case - probably a jig and reflow over or hot plate is the only option - I don't think hand solder in this case is an option or you way better than the average user at doing this if you can.
Dave On Monday, August 25, 2014 12:08:25 PM UTC-5, Vince Mulhollon wrote: > > On Monday, August 25, 2014 10:09:35 AM UTC-5, monahanz wrote: >> >> soldering two SMD connectors to an S100 board is not that hard. >> > The part I find completely agonizing about that board is its TWO > connectors on two rigid PCBs.. > > I pretty much LOL at surface mount since I've been doing it for RF stuff > since the 80s and I find it easier than thru-hole but to attach both > connectors with less than perhaps 0.1 mm accuracy to smoothly attach would > require me to build a little aluminum mounting jig or something. Maybe for > the price of those boards it would be cheaper to milling machine away the > PCB so I could plug connectors into a machined board, then lay the board on > top of the S100 card, then solder the connectors to the S100 board while > its plugged in to the sacrificial board. > > See if it was just one connector, then misalignment isn't an issue. Or if > one connector (or both) was a short cable. Or if via the peculiarities of > the board we could get away with just one connector and not install the > other. Or if a thru-hole connector were available. > > I imagine soldering in both connectors and they look visually lined up but > the board won't physically plug in. Not enough just to get one connector > with no opens/shorts but to get two in perfect alignment. No trapezoids or > parallelograms, perfect distance apart, etc. > > Maybe use screw holes first to mount it and don't start soldering until it > lines up and then hope it doesn't shift at the final removal? Or is there > a technique involving superglue? Given the price of indium solder I don't > like the idea of using it to attach the two connectors but that stuff and > the hot plate / frying pan technique might work. Then the solder on the > board might not melt while I'm attaching the connectors. > > I'd like to see a proto-ish board that has the 6502-ish logic to give and > receive control of the bus. Everything but the 6502 and its support. Then > solder in a "fill in the blank" that manipulates the S100 bus lines by > either hardware (and glue) or software (and I/O pins) to connect a CPU. I > have to think for a second, certainly you need less than 100 I/O lines to > talk S-100. And to talk CPU-ish takes less than 40 pins. So more than 24 > I/O pins but less than 40 to talk? > -- You received this message because you are subscribed to the Google Groups "N8VEM-S100" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
