New pcb design for S-100 prototype board available

Here's the specs I used from my Imsai 8080 backplane. 22slot , 8.5" x 17", 0.062"(1/16") thickness, 2 layer pcb, 2oz copper(approx), plated thru holes, green solder mask top and bottom, white silkscreen top, Hot Air Solder Level, 15day lead time. I currently use a place called General Circuits Co.Ltd(China), www.pcbcart.com. They've been providing a good quality service. Imagineering is rather expensive if you ask me as most of them places can be. For quick prototype, I also use Barebonespcb.com The Imsai backplane is supported by a grid of standoff's at every other slot position along both edges on the steel chassis. This is how it retains it's strength when inserting many cards into the system. They didn't need to make it any thicker. The only time I had thicker backplane pcbs is for an industrial system, CPCI or VME systems, --which this isn't-- then it's wise to make a 1/8" or 3/16" backplane. At my last job,Lucent, our telecom backplanes were 1/2" thick. This is usually the result of a 8,10,12 layer or more pcb. It also offers a system which can withstand the rigors of an unpredictable environment. The Imsai, Altair, and the like are just home systems. The copper thickness is estimated but it has to be more than the standard 1oz since this has a high current capacity. I can recheck the cost projections for a thicker copper layer just in case. All the sockets have gold plated contacts and are very good quality. Good thing you mentioned the sockets. I was using a supplier which has a dwindling supply(JDR)--checked it recently-- I hate when that happens. They don't even have enough left over to make one backplane --uuggh-- and can't even bother to resupply. I had to source another supplier I use for other stuff (Sullins Electronics). They have plenty but they cost alittle more. To make it still reasonable, the batch order would have to be 25 pieces at least and then the connectors would be down to $15each.(I should double check the shipping again). The problem with dealing directly with the vendors is that the prices they quote can mysteriously fluctuate depending on the lifespan of a gnat circumnavigating a buffalo's butt. So a kit price would be way more expensive for a 22slot backplane But you can always buy a few connectors at a clip and worry about filling the backplane later. Hey do I get a commission, now that I gave you some more suppliers :) =Dan [ beauty is in the eye of the beer holder ] [ http://ragooman.home.comcast.net/ ] Grant Stockly wrote: