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#1
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Large PCB source for dead bug homebrewing?
Many years ago (like, 20) I bought many 24" x 24" sheets of
single-sided PCB that I've been using to homebrew dead-bug style and for other activities like soldering together little shielded boxes. Probably mail-order from Fair Radio.I'm sure I paid very little for the stuff at the time, probably a few bucks a sheet. Now my stash is almost gone. Anyone care to recommend a good cheap supplier for similar single-sided PCB? I'm not picky as to phenolic vs glass-epoxy or whatever, I just need a good ground plane. Big pieces are good but I can live with little pieces too. The stuff I got 20 years ago was, for some reason, pre-tinned. (Maybe this is why it was so cheap?). That was nice because I don't have to clean off my dirty fingerprints when coming back to a project after a few weeks or a few years :-). Pre-tinned is a big plus. |
#3
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Hello Tim,
See if there is a PCB manufacturer within resonable driving distance and ask for scraps. That's how I got a huge stash decades ago. Single and double sided, the good stuff (FR4). But it has to be picked up, in my case they wouldn't have gone through the trouble of packaging and mailing it. Basically it had to be no more effort on their part than a walk to the dumpster would have been. Mine weren't tinned though. Also, I am not sure if constantly touching a pre-tinned board during experiments would be too healthy. Regards, Joerg http://www.analogconsultants.com |
#4
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Hello Tim,
Just one more thought: I use "living-bug" arrangements almost exclusively. Every once in a while I cut up some strips so they fit the most popular "underbellies" of chips. Then I glue the strips onto the large panel and the chips on top of the strips in a rider's fashion. Ground connection can be achieved by slightly bending down a pin, the rest gets wired up Sauerkraut style like usual. When stray capacitance is critical I take washed wood strips instead of copper clad. Makes for a really nice excuse to eat another Haagen Dasz. This avoids having to think in reverse pinout and it often looks nicer, too. Plus you can still see the "CD4007" on the chip. Regards, Joerg http://www.analogconsultants.com |
#5
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In article ,
says... Hello Tim, Just one more thought: I use "living-bug" arrangements almost exclusively. Every once in a while I cut up some strips so they fit the most popular "underbellies" of chips. Then I glue the strips onto the large panel and the chips on top of the strips in a rider's fashion. Ground connection can be achieved by slightly bending down a pin, the rest gets wired up Sauerkraut style like usual. When stray capacitance is critical I take washed wood strips instead of copper clad. Makes for a really nice excuse to eat another Haagen Dasz. This avoids having to think in reverse pinout and it often looks nicer, too. Plus you can still see the "CD4007" on the chip. Or you can just bend all but the ground pins outward from the base of the chip (e.g., www.speakeasy.net/ ~jmiles1/ke5fx/492ap/large/close1.jpg). The pins won't break if you don't flex them more than once or twice. Sometimes I'll use a drop of cynaoacrylate adhesive to hold the chip into place if there are few or no grounded pins, but it's rarely necessary. This also works for SOICs and even TSSOPs, as long as you don't bend the pins more than once. -- jm ------------------------------------------------------ http://www.qsl.net/ke5fx Note: My E-mail address has been altered to avoid spam ------------------------------------------------------ |
#6
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Hello John,
Or you can just bend all but the ground pins outward from the base of the chip (e.g., www.speakeasy.net/ ~jmiles1/ke5fx/492ap/large/close1.jpg). The pins won't break if you don't flex them more than once or twice. But then I won't have an excuse to eat another Haagen Dasz bar :-( Regards, Joerg http://www.analogconsultants.com |
#7
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From: "Tim Shoppa" on Tues,May 3 2005 10:22 am
Many years ago (like, 20) I bought many 24" x 24" sheets of single-sided PCB that I've been using to homebrew dead-bug style and for other activities like soldering together little shielded boxes. Probably mail-order from Fair Radio.I'm sure I paid very little for the stuff at the time, probably a few bucks a sheet. Now my stash is almost gone. Anyone care to recommend a good cheap supplier for similar single-sided PCB? I'm not picky as to phenolic vs glass-epoxy or whatever, I just need a good ground plane. Big pieces are good but I can live with little pieces too. Ebay might be good as someone else suggested. The best bet for low CO$T material is to sweet-talk a PCB maker for left- overs...if one is in your neighborhood. I've gotten fairly good prices from www.circuitspecialists.com on double-sided stock (comes in protective plastic envelope). The stuff I got 20 years ago was, for some reason, pre-tinned. (Maybe this is why it was so cheap?). That was nice because I don't have to clean off my dirty fingerprints when coming back to a project after a few weeks or a few years :-). Pre-tinned is a big plus. Cleaning OLD PCB stock the "green" way - Sprinkle any kind of table salt on the PCB stock, then take half a lemon and rub it on the salt. Most of the blackened oxide will disappear! I tried that late last year on some 4" x 8" double-sided phenolic substrate PCB stock after seeing all those "green" site remarks that I didn't really believe. It WORKS! :-) Those pieces had been sitting in the back of the workshop for about 35 years. I did "cheat" a bit. Have a year-round producing lemon tree and my wife had some coarse salt left over from a canning experiment. Zero cost trial...lemons at the markets can run 50 cents each. The residue can easily wash down the sink, don't need any gloves, nothing toxic. Result is easily solderable although for best appearance, some cleaning with a bleach-containing kitchen cleanser will make it shiny and spotless. |
#8
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"Joerg" wrote in message ... Hello Tim, See if there is a PCB manufacturer within resonable driving distance and ask for scraps. That's how I got a huge stash decades ago. Single and double sided, the good stuff (FR4). But it has to be picked up, in my case they wouldn't have gone through the trouble of packaging and mailing it. Basically it had to be no more effort on their part than a walk to the dumpster would have been. Mine weren't tinned though. Also, I am not sure if constantly touching a pre-tinned board during experiments would be too healthy. Why is that? Lead? I thought that paint with lead in it was a lot worse. Regards, Joerg http://www.analogconsultants.com |
#9
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"Joerg" wrote in message om... Hello Tim, Just one more thought: I use "living-bug" arrangements almost exclusively. Every once in a while I cut up some strips so they fit the most popular "underbellies" of chips. Then I glue the strips onto the large panel and the chips on top of the strips in a rider's fashion. Ground connection can be achieved by slightly bending down a pin, the rest gets wired up Sauerkraut style like usual. When stray capacitance is critical I take washed wood strips instead of copper clad. Makes for a really nice excuse to eat another Haagen Dasz. This avoids having to think in reverse pinout and it often looks nicer, too. Plus you can still see the "CD4007" on the chip. Back in the early '70s I got some prototype boards from a company that made aircraft receivers. They used four push-in pins, one for each lead of the four corners of the IC. Two of these are usually power and ground, pins 7 or 8 and 14 or 16. These four hold the chip up off the board, and the other pins are wired spaghetti style, which I presume is the same as your sauerkraut style. Speaking of this.. Last Sunday at our monthly compouter club meeting someone donated a homemade S-100 system to the consignment table, but no one bought it, so it ended up on the freebies table later, probably then into the trash later. It had a chassis and box pop riveted together, and the S-100 bus was all wire wrapped. A lotta love and time went into building that way back in the late '70s. Regards, Joerg http://www.analogconsultants.com |
#10
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"John Miles" wrote in message ... In article , says... Hello Tim, Just one more thought: I use "living-bug" arrangements almost exclusively. Every once in a while I cut up some strips so they fit the most popular "underbellies" of chips. Then I glue the strips onto the large panel and the chips on top of the strips in a rider's fashion. Ground connection can be achieved by slightly bending down a pin, the rest gets wired up Sauerkraut style like usual. When stray capacitance is critical I take washed wood strips instead of copper clad. Makes for a really nice excuse to eat another Haagen Dasz. This avoids having to think in reverse pinout and it often looks nicer, too. Plus you can still see the "CD4007" on the chip. Or you can just bend all but the ground pins outward from the base of the chip (e.g., www.speakeasy.net/ ~jmiles1/ke5fx/492ap/large/close1.jpg). The pins won't break if you don't flex them more than once or twice. Sometimes I'll use a drop of cynaoacrylate adhesive to hold the chip into place if there are few or no grounded pins, but it's rarely necessary. This also works for SOICs and even TSSOPs, as long as you don't bend the pins more than once. -- jm What's the board in? A receiver? What's it do? |
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