dnewton@carroll1.UUCP (Dave 'Post No Nicknames' Newton) (11/13/89)
I don't like routing PCBs by hand, but I don't like wire-wrapping large boards either. (Manual tool at this point) Is either one of them better? I've heard that a lot of critical circuits are wire-wrapped for reliability. Is this true? Is wire wrap harder to debug? Just wondering. Oh, can anyone recommend a cheap auto-routing PCB design package? -- David L. Newton | uunet!marque!carroll1!dnewton | The Raging Apostle-- (414) 524-7343 (work) | dnewton@carroll1.cc.edu | for the future-- (414) 524-6809 (home) | 100 NE Ave, Waukesha WI 53186 | for the world. "Isn't it fun to take two unrelated sentences and mix the batter lightly?" -me
peg@psuecl.bitnet (11/13/89)
In article <850@carroll1.UUCP>, dnewton@carroll1.UUCP (Dave 'Post No Nicknames' Newton) writes: > > Oh, can anyone recommend a cheap auto-routing PCB design package? > 1) For what computer? 2) What do you consider cheap?
dnewton@carroll1.UUCP (Dave 'Post No Nicknames' Newton) (11/13/89)
In article <65276@psuecl.bitnet> peg@psuecl.bitnet writes: >In article <850@carroll1.UUCP>, dnewton@carroll1.UUCP (Dave 'Post No Nicknames' Newton) writes: >> >> Oh, can anyone recommend a cheap auto-routing PCB design package? >> > 1) For what computer? I don't care, but preferably somthing DOS, GEM (i.e. IBM or Atari ST), or Amiga. Don't wanna buy a 386i or Sun-4. > 2) What do you consider cheap? Well, Tango PC w/ autoroute costs around $1000, so I'm looking for something between $500-$1500. The cheaper the better. Doesn't have to have a whole lot of features, I just need it to get the job done. I would like it to output to a plotter _or_ printer though. -- David L. Newton | uunet!marque!carroll1!dnewton | The Raging Apostle-- (414) 524-7343 (work) | dnewton@carroll1.cc.edu | for the future-- (414) 524-6809 (home) | 100 NE Ave, Waukesha WI 53186 | for the world. "Isn't it fun to take two unrelated sentences and mix the batter lightly?" -me
waw103@tijc02.UUCP (Alan Watson ) (11/13/89)
From article <850@carroll1.UUCP>, by dnewton@carroll1.UUCP (Dave 'Post No Nicknames' Newton): > > I don't like routing PCBs by hand, but I don't like wire-wrapping large > boards either. (Manual tool at this point) > Is either one of them better? I've heard that a lot of critical circuits > are wire-wrapped for reliability. Is this true? > GENERALLY SPEAKING, Good wire-wrap is more reliable. PCBs suffer because they aren't very flexible. Any excessive bending will break solder joints, possibly crack foil traces. Also you have to worry about cold-solder joints, acid corrosion, etc. A good wire-wrap connection is gas-tight so corrosion won't degrade the connection and of course it can withstand quite a bit of flexing. Naturally it is pretty easy to change a wire-wrapped layout. I think that you need a good wire-wrap gun to get consistently good connections, plus it will really speed up the work. waw
forbes@aries.uiuc.edu (Jeff Forbes) (11/14/89)
Advanced Microcomputer Systems, Inc. has a complete PCB system for the PC for $500.00. Their phone number is (305)975-9515. It includes schematic capture, PCB layout, and autorouter programs. They have a free demo package. I have the PCB layout program and it works fine. The plotting program could be a little better though. Jeff Forbes
deanr@sco.COM (Dean Reece) (11/14/89)
In article <850@carroll1.UUCP> dnewton@carroll1.cc.edu (Dave 'Post No Nicknames' Newton) writes: > > I don't like routing PCBs by hand, but I don't like wire-wrapping large >boards either. (Manual tool at this point) > Is either one of them better? I've heard that a lot of critical circuits >are wire-wrapped for reliability. Is this true? Is wire wrap harder to debug? > > Just wondering. > > Oh, can anyone recommend a cheap auto-routing PCB design package? Well, I've experimented with several techniques and my favorite is still point to point wiring using 30 guage wire-wrap wire. Its sloppy looking, but I find it easier to debug/correct/modify than either wire wrap or PCBs. The only real problem I have with PCBs is the ammount of time it takes to lay on out. I need several layers, or lots-o-feedthroughs, so I came up wuth an alternative: Figure out how many layers you really need (usually 1 or 2 for power and 1 or 2 for busses & signals) Lay out each layer and produce a drill pattern. Drill as many SINGLE SIDED PCB Blanks as layers, (do this by drilling all of them at one time, or you'll never fit them together) then etch each PCB with a layer. You can then use wire wrap sockets to assemble the thing. (You solder one layer on at a time.) If you want to get fancy, you can make the TOP layer (component side) a double sided board, which allows Double sided Edge card connectors, and/or better shelding. One nice side effect is that you can leave some of the Unknowns out of the design and wire-wrap them later, since you'll have about 1/2" of the WW pins remaining. This hybrid idea works well (unless you goof on an internal layer) since you don't have to work so hard to keep the paths on 1 or 2 layers only. I usually made the top layer a double sided board with connectors and power busses ONLY. This way, the decoupling caps need only go as deep as the 1st board. The next board or two were the 'simple' paths like data and address busses. The outer layer(s) were for the more complex (read: likely to be wrong) connections. Sometimes this outer layer was omitted and done only in Wire Wrap or point to point. Well, thats my 2 cents worth - hope it helps - I would be interested in other ideas for simple, single unit production. ______________________________________________________________________ | Dean Reece Member Technical Staff |"The flames are all long gone | | The Santa Cruz Operation 408/458-1422 | but the pain lingers on" | |___________deanr@sco.com_______________|___________________Pink_Floyd_|
daveh@cbmvax.UUCP (Dave Haynie) (11/14/89)
in article <852@carroll1.UUCP>, dnewton@carroll1.UUCP (Dave 'Post No Nicknames' Newton) says: >>> Oh, can anyone recommend a cheap auto-routing PCB design package? > Well, Tango PC w/ autoroute costs around $1000, so I'm looking for > something between $500-$1500. Pro-Board for the Amiga is about $450.00 list, but it doesn't have what I'd consider a real autorouting facility. What the call "autoroute" I'd call basically an "auto-stitch". If you're stitching up a bus or some relatively regular network, you can go into "autoroute" mode and click from pad to pad while it does the routing between the pads. Works OK for this simple stuff, but it's no good for anything very diagonal or long and complicated. What I call real autoroute is what we get on the dedicated Calay machines here -- dump it in the autorouter when you go home, and next morning it's done, 100% routed. Pro-Board also only supports ups to 4 layer boards with no inner-layer traces. It does support surface mount parts. The production-ready output is in Gerber format, though as I recall you can get dot matrix or HPGL output at least for preview. I wrote a review of this one for Amiga Sentry awhile back. It's certainly servicable, but it's not up to the Calay or SciCards level (that's what our PCB layout guys use here at work). Pro-Net takes the same netlist format as Calay. There's also one for the Amiga called PCLO which I haven't looked at yet, though I just got one recently. This was apparently the first one for the Amiga, though I'm not sure if it's still being supported or not (I know it's author is still quite active in the Amiga community, though the company seems to have vanished). I gather they have two versions of PCLO, so this could be the cheapest layout package around, though I doubt there's any form of autorouting. When I check it out I'll be sure to mention it if it's something in the "don't miss" category. > David L. Newton | uunet!marque!carroll1!dnewton | The Raging Apostle-- -- Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: hazy BIX: hazy Too much of everything is just enough
kyoung@auspex.auspex.com (Ken Young) (11/15/89)
In article <850@carroll1.UUCP> dnewton@carroll1.cc.edu (Dave 'Post No Nicknames' Newton) writes: > I don't like routing PCBs by hand, but I don't like wire-wrapping large >boards either. (Manual tool at this point) > Is either one of them better? I've heard that a lot of critical circuits >are wire-wrapped for reliability. Is this true? Is wire wrap harder to debug? Rules of thumb(s): Wire wrap is less reliable. Wire wrap is cheaper for one board, but if you need more than one, make it a PCB. Ken Young uunet!auspex!kyoung