Apparently Ian is building an Apple II card for VCF, and doesn't like most of the current prototype card offerings -- either the layout is...deficient, or they're not regularly available. I laid out a simple pad-per-hole board: http://i.imgur.com/G5QOATi.png I have a small prototype quantity on order, but I'll probably be ordering 50 or 100 in the near future, if anyone is interested. Thanks, Jonathan
On Fri, Jun 24, 2016 at 9:42 PM, Systems Glitch via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
Apparently Ian is building an Apple II card for VCF, and doesn't like most of the current prototype card offerings -- either the layout is...deficient, or they're not regularly available. I laid out a simple pad-per-hole board:
http://i.imgur.com/G5QOATi.png
I have a small prototype quantity on order, but I'll probably be ordering 50 or 100 in the near future, if anyone is interested.
Thanks, Jonathan
very nice One item I would suggest, after looking at the routing of power bus, but without looking at the bottom side of your pcb yet, so I don't know if you had already done so, would be to make the ground bus encircle the entire board as well, but then have both ends of the ground bus connected to the ground pin on the card edge It can hard to create copper fill for the ground layer on a prototype board, when the parts layout is unknown But that one little step can still help avoid ground loops This problem can even happen on homebrew projects Dan
One item I would suggest, after looking at the routing of power bus, but without looking at the bottom side of your pcb yet, so I don't know if you had already done so, would be to make the ground bus encircle the entire board as well, but then have both ends of the ground bus connected to the ground pin on the card edge It can hard to create copper fill for the ground layer on a prototype board, when the parts layout is unknown But that one little step can still help avoid ground loops This problem can even happen on homebrew projects
Thanks for the feedback! There is indeed a ground trace on the bottom side, but it doesn't connect back to the ground pin. I could see ground loop issues popping up with analog circuits on the card, but you'd probably want to use a star ground there anyway. I could probably run the ground trace the rest of the way around, but I might have to remove a row of pads above the edge connector area. Thanks, Jonathan
participants (2)
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Dan Roganti -
Systems Glitch