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Ed Price wrote:
"Michael A. Terrell" wrote in message ... Ed Price wrote: "John D. Farr" wrote in message ... It seems that if one owns the equipment, he has a right to the docs for it. John Would that were true! g Yeah, in days of old, equipment always came with at least a schematic, even if it was glued to the inside of the wood case. But along the way, stuff got a lot more complicated. In 1960 or so, when you bought a Tek 555 scope, you got a full manual too, a couple of inches of docs. But the pressure builds to trim costs, and by the 70's, you spend $15k for an instrument, and all you get is an Operational Manual. The two-inch thick Service Manual, with theory, parts list, diagnostic trees, and typical waveforms is $100 extra. If I want the full docs now for say, an HP-8566B or an HP-8471A, I better bring a cart. There's an Operator's Manual, a Service Manual, a Programmers Manual, and a Parts List, Spares List & Calibration Manual. And they each fill a 3" notebook binder! Actually, the days of big manuals may be gone already. New equipment now is much more disposable; you don't find a master tech troubleshooting a complex equipment. Instead, they slap on an IEEE-488 diagnostic cable, run the factory supplied calibration and diagnostic, and, if it can't be fixed in software, it likely gets declared too expensive to fix. Junk it! And if you think that's gonna mean a new golden age of surplus, you're wrong. Modern gear is more computer than anything else. There's not much you can do when you see the signal go into a proprietary chip, and nothing comes out. And the construction is now all surface-mount stuff, with trace spacing so close it looks like a Moiré pattern. I defy you to probe any ONE trace. OK, so maybe you like using a microscope. g Ed WB6WSN Fine pitch surface mount isn't that hard to work on, after a little training. You do need a steady hand, and the right tools to do good work. I spent four years doing fine pitch surface mount PC board work, both testing and repairing boards that make a motherboard for a PC look simple. Because of my poor vision I had to use a stereo microscope to see the solder bridges and solder joints that cracked while the board was cooling in the reflow oven. -- Michael A. Terrell Central Florida Mike: I'm glad you agree with me, even if I had to read between the lines to find it! I'm pretty acquainted with fine-pitch surface-mount assembly. For years, my company has been doing military command and communications products, all with multi-layer boards and surface mount and flexible circuitry. We got dozens of nimble-fingered, tiny ladies working micro-manipulators under hideously expensive stereo microscopes or even video-cam microscopes. Robotic assemblers pick & place with a speed that's amazing. We do computer optical scanning of assembled boards to check for faults. And when a board doesn't work right, we don't spend much time trying to fix it. If a tech can't fix it in a few minutes, she harvests a couple of expensive parts and the rest gets shredded. And all my experience with a soldering iron and perf boards and wire wrap simply means nothing in this world. Manual mucking around on equipment like this scares the hell out of quality guys. They figure that anything you fix is more than offset by your big, clumsy intrusive actions. Up to the point where you touch the board, they figure they have most everything under control about that item's history. You go at that board, poking and prodding, sticking a needle-point probe who knows where. (Just for fun, if you have a probe with a 0.01" diameter tip, which is about 7.8 x 10^^-5 square inches, and you push with 3 pounds force, you are exerting some 38,000 psi on the target!) So don't tell me you never broke anything just trying to find the initial problem. Let's see, it's not hard to work on. All you need is a stereo microscope and a reflow oven, and some more "right tools." So, should the beginner start saving for the oven or the microscope first? g Ed WB6WSN My favorite SMD tool is a modified Exacto knife carefully shaped on a sharpening stone to fit between the pins, and the sharp point rounded off so you don't scratch the fiberglass board. Some of the boards were 16 layer, and cost $8,000 to build and test. They were part of the L-3com/Microdyne RCB-2000 telemetry receivers. As far as tools for surface mount work I recommend some type of magnifier, a good quality adjustable soldering iron. (we used the Ungar "Loner" series) with a small tip and very fine solder. We used Ersin/Mulitcore that looked like a hair. A small bottle with RMA flux, and a hypodermic needle to apply small amounts of extra flux. The smallest solder wick you can get to clean bad solder off the bad joints, and use the wet wick method of dipping the braid into the flux and use it wet so it reduces heat damage to the board. Also, you need to leave about 1/16" of solder saturated braid when you clip off the used part. That way you transfer the heat to the joint, not the circuit board. Like any other repair/rework, it just takes the right preparation, a steady pair of hands, and common sense. I am currently out of work, after L-3Com closed the Microdyne plant and moved it to the rust belt. A doctor at the VA hospital in Gainsville recently diagnosed me with carpal tunnel in my right wrist and nerve damage to two fingers of my left hand so its unlikely I will get a lot of use out of those skills, now. I have been trying to find some contract board repair, or small assembly jobs I can do from home. The only electronics work left in the area is Lockheed-Martin, and they have been shipping jobs to Texas. I have a decent shop, and I have been working to make it more usable, under the circumstances. -- Michael A. Terrell Central Florida |
Ed Price wrote:
"Michael A. Terrell" wrote in message ... Ed Price wrote: "John D. Farr" wrote in message ... It seems that if one owns the equipment, he has a right to the docs for it. John Would that were true! g Yeah, in days of old, equipment always came with at least a schematic, even if it was glued to the inside of the wood case. But along the way, stuff got a lot more complicated. In 1960 or so, when you bought a Tek 555 scope, you got a full manual too, a couple of inches of docs. But the pressure builds to trim costs, and by the 70's, you spend $15k for an instrument, and all you get is an Operational Manual. The two-inch thick Service Manual, with theory, parts list, diagnostic trees, and typical waveforms is $100 extra. If I want the full docs now for say, an HP-8566B or an HP-8471A, I better bring a cart. There's an Operator's Manual, a Service Manual, a Programmers Manual, and a Parts List, Spares List & Calibration Manual. And they each fill a 3" notebook binder! Actually, the days of big manuals may be gone already. New equipment now is much more disposable; you don't find a master tech troubleshooting a complex equipment. Instead, they slap on an IEEE-488 diagnostic cable, run the factory supplied calibration and diagnostic, and, if it can't be fixed in software, it likely gets declared too expensive to fix. Junk it! And if you think that's gonna mean a new golden age of surplus, you're wrong. Modern gear is more computer than anything else. There's not much you can do when you see the signal go into a proprietary chip, and nothing comes out. And the construction is now all surface-mount stuff, with trace spacing so close it looks like a Moiré pattern. I defy you to probe any ONE trace. OK, so maybe you like using a microscope. g Ed WB6WSN Fine pitch surface mount isn't that hard to work on, after a little training. You do need a steady hand, and the right tools to do good work. I spent four years doing fine pitch surface mount PC board work, both testing and repairing boards that make a motherboard for a PC look simple. Because of my poor vision I had to use a stereo microscope to see the solder bridges and solder joints that cracked while the board was cooling in the reflow oven. -- Michael A. Terrell Central Florida Mike: I'm glad you agree with me, even if I had to read between the lines to find it! I'm pretty acquainted with fine-pitch surface-mount assembly. For years, my company has been doing military command and communications products, all with multi-layer boards and surface mount and flexible circuitry. We got dozens of nimble-fingered, tiny ladies working micro-manipulators under hideously expensive stereo microscopes or even video-cam microscopes. Robotic assemblers pick & place with a speed that's amazing. We do computer optical scanning of assembled boards to check for faults. And when a board doesn't work right, we don't spend much time trying to fix it. If a tech can't fix it in a few minutes, she harvests a couple of expensive parts and the rest gets shredded. And all my experience with a soldering iron and perf boards and wire wrap simply means nothing in this world. Manual mucking around on equipment like this scares the hell out of quality guys. They figure that anything you fix is more than offset by your big, clumsy intrusive actions. Up to the point where you touch the board, they figure they have most everything under control about that item's history. You go at that board, poking and prodding, sticking a needle-point probe who knows where. (Just for fun, if you have a probe with a 0.01" diameter tip, which is about 7.8 x 10^^-5 square inches, and you push with 3 pounds force, you are exerting some 38,000 psi on the target!) So don't tell me you never broke anything just trying to find the initial problem. Let's see, it's not hard to work on. All you need is a stereo microscope and a reflow oven, and some more "right tools." So, should the beginner start saving for the oven or the microscope first? g Ed WB6WSN My favorite SMD tool is a modified Exacto knife carefully shaped on a sharpening stone to fit between the pins, and the sharp point rounded off so you don't scratch the fiberglass board. Some of the boards were 16 layer, and cost $8,000 to build and test. They were part of the L-3com/Microdyne RCB-2000 telemetry receivers. As far as tools for surface mount work I recommend some type of magnifier, a good quality adjustable soldering iron. (we used the Ungar "Loner" series) with a small tip and very fine solder. We used Ersin/Mulitcore that looked like a hair. A small bottle with RMA flux, and a hypodermic needle to apply small amounts of extra flux. The smallest solder wick you can get to clean bad solder off the bad joints, and use the wet wick method of dipping the braid into the flux and use it wet so it reduces heat damage to the board. Also, you need to leave about 1/16" of solder saturated braid when you clip off the used part. That way you transfer the heat to the joint, not the circuit board. Like any other repair/rework, it just takes the right preparation, a steady pair of hands, and common sense. I am currently out of work, after L-3Com closed the Microdyne plant and moved it to the rust belt. A doctor at the VA hospital in Gainsville recently diagnosed me with carpal tunnel in my right wrist and nerve damage to two fingers of my left hand so its unlikely I will get a lot of use out of those skills, now. I have been trying to find some contract board repair, or small assembly jobs I can do from home. The only electronics work left in the area is Lockheed-Martin, and they have been shipping jobs to Texas. I have a decent shop, and I have been working to make it more usable, under the circumstances. -- Michael A. Terrell Central Florida |
Not necessarily. Manuals are sometimes considered to be part of the cost of
producing a product. I once worked at a place where we charged for copies of manuals - but if someone came in and wanted one we would let them borrow one to copy. The cost to buy one was to cover our costs of repro and time to deal with the transaction. That was a while ago, before the web was so accessible to the public. Nowadays there are plenty of companies which provide their manuals for free download. However, if you are SCO or RIAA, all bets are off... "Dee D. Flint" wrote in message .com... "Nocturnal1" wrote in message ... If I had my druthers, there would be no copyright law and everything would be freely available for downloading... Nobody would write any new material in that case. It wouldn't be worth their time and effort. Dee D. Flint, N8UZE |
On Fri, 26 Sep 2003 23:00:41 GMT, "Dee D. Flint" wrote:
"Nocturnal1" wrote in message ... If I had my druthers, there would be no copyright law and everything would be freely available for downloading... Nobody would write any new material in that case. It wouldn't be worth their time and effort. Not necessarily. The books in the Baen Free Library (freely downloadable, no copy protection mechanisms whatsoever) tend to outsell both their own previous sales and those of books of similar age and similar previous sales by a factor of 4. Jasper |
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