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- Path: sparky!uunet!utcsri!torn!news.ccs.queensu.ca!qucdn!leek
- Organization: Queen's University at Kingston
- Date: Sunday, 26 Jul 1992 14:31:20 EDT
- From: <LEEK@QUCDN.QueensU.CA>
- Message-ID: <92208.143120LEEK@QUCDN.QueensU.CA>
- Newsgroups: sci.electronics
- Subject: Re: 0.100" spacing
- References: <1992Jul24.135835.21402@cci632.cci.com>
- <1992Jul26.065031.10461@uniwa.uwa.edu.au>
- Lines: 43
-
- In article <1992Jul26.065031.10461@uniwa.uwa.edu.au>, gude@uniwa.uwa.edu.au
- (David J W Emrich) says:
-
- >.... stuff deleted.... (About lining up dips for drilling)
- >
- >the DIPs later on. My solution was to make up several jigs to use when
- >drilling the IC holes.
- >
- >First, get hold of an old commercial PCB that you don't want any more,
- >with lots of DIPs on it. Preferrably at least a 22-pin and a 48-pin DIP
-
- or a good piece of Breadboard that already have grids of holes lined up
- at 0.1". Easier that way.
-
- >(I think 22 is the longest .3" wide DIP and 48 is the longest .6" wide
-
- There are manufacturers making 28 pins DIP's at 0.3" to save space.
- You are probably right about 48 pins package. Most of the higher pin
- count chips goes to PLCC or PGA.
-
- >DIP). The idea is to find the longest available DIPs at whatever widths
- >you use. You can use the 22pin jig to drill anywhere from 8-pin up to
- >22-pin DIPs.
-
- >To use the jigs, just line them up with the copper pads, by holding the
- >PCB up to the light, and clamp the jig (parallel clamps are the best,
- >but G-clamps are quite OK). Then drill away!
-
- I used to do the same using breadboard as jigs. These days I leave a
- donut hole in the middle of the pad to guide the drill bit, but hey
- I got a new prescription recently. :)
-
- >
- >It's still fiddly, but it is quite a bit quicker than eye-sight
- >guessing, and a lot less optically stressful!
- >
- >Hope this is of some use.
- >
- >David Emrich
- >gude@uniwa.uwa.edu.au
-
- K. C. Lee
- Elec. Eng. Grad. Student
-