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John-Del <ohger1s@aol.com>: Dec 18 09:18AM -0800 On Friday, December 18, 2015 at 7:37:37 AM UTC-5, Mark Zacharias wrote:   > Prefer direct-coupled amps (with a competent protection circuit!) > Mark Z.   Funny how certain things trigger a memory of something forgotten for years. I had a Hitachi brand receiver that the customer said blew out several speakers on one side. I checked the outputs, nothing shorted so I hooked up some cheap TV speakers at low volume and there was no DC to speak of on either side and it was clean and clear. I let it run a couple of hours and suddenly there was a loud hum, pop, and one TV speaker that puked it's voice coil. This was direct coupled amp with no type of speaker protection. Ended up junking it.

Cydrome Leader <presence@MUNGEpanix.com>: Dec 18 08:31PM > What? You don't like my method of documenting changes? > <http://members.cruzio.com/~jeffl/k6bj/K6BJ%20Repeater/slides/Documentation.html> > I think it's been like that since at least 2001.   ha. Love the metal can transistor diagram. At least these aren't drawn on paper bags or cardboard and then thrown away.   > Incidentally, I use a special ink for the purpose, that fades to > invisibility in about a year. It helps keep the manuals nice and > clean.   They should make heated pens for writing on thermal paper.

Jeff Liebermann <jeffl@cruzio.com>: Dec 18 02:16PM -0800 On Fri, 18 Dec 2015 20:31:53 +0000 (UTC), Cydrome Leader >> I think it's been like that since at least 2001.   >ha. Love the metal can transistor diagram. At least these aren't drawn on >paper bags or cardboard and then thrown away.   That scribbling wasn't one of mine. I usually draw an isometric scribbling of the transistor or IC so that one can tell if it's a top or bottom view. I think the red markings on the various drawings are mine. Red is useful because it disappears when copied.   >> invisibility in about a year. It helps keep the manuals nice and >> clean.   >They should make heated pens for writing on thermal paper.   Ummm... They do. It's called a soldering iron. However, there's a trick to using a soldering iron for writing. Be sure to grab the correct end of the soldering iron. The rest is self evident and easy.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Cydrome Leader <presence@MUNGEpanix.com>: Dec 18 11:28PM > scribbling of the transistor or IC so that one can tell if it's a top > or bottom view. I think the red markings on the various drawings are > mine. Red is useful because it disappears when copied.   What the color of highlighter that would copy solid black even though you could still read the original?   The copiers here are just color scanner/printers so they don't have the same spectral sensitivity as the old machines so I can't test.     > Ummm... They do. It's called a soldering iron. However, there's a > trick to using a soldering iron for writing. Be sure to grab the > correct end of the soldering iron. The rest is self evident and easy.   Too hot and the thermal paper cycles back to white. It does weird things when heated to the transition temp range.

Jeff Liebermann <jeffl@cruzio.com>: Dec 18 04:00PM -0800 On Fri, 18 Dec 2015 23:28:59 +0000 (UTC), Cydrome Leader   >What the color of highlighter that would copy solid black even though you >could still read the original?   I don't know and too lazy to test it on my copier.   Interesting stuff: <http://www.protectedpaper.com/category_s/17.htm>   >The copiers here are just color scanner/printers so they don't have the >same spectral sensitivity as the old machines so I can't test.   I have an (old) Canon PC785 mono copier which should work. However, I don't have any highlighters to try.   >> correct end of the soldering iron. The rest is self evident and easy.   >Too hot and the thermal paper cycles back to white. It does weird things >when heated to the transition temp range.   Too hot and the paper catches fire. As I recall, the paper was black or brown before it started burning. I just tried it with some thermal receipt printer paper. It didn't go back to white.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

mroberds@att.net: Dec 19 01:04AM > Anyone care to share their experience on the correct approach to > troubleshooting?   Maybe I've been hanging out around too many manager or business types, but I'd suggest:   Find out if a working new (or used) example of the item in question is available, and what it costs.   Under a certain amount, it won't pay to spend time fixing it, unless there are some other circumstances involved. (It was grandma's radio, or whatever.)   Between that amount and some other, really high amount, it might pay to spend time fixing it.   Above that really high amount, they are either wanting confirmation that it is broken, so they can persuade their boss to buy a new one, OR hoping to blame you for an inability to fix it, so *you* have to buy the new one.   Just because you're paranoid doesn't mean that they *aren't* out to get you.   Matt Roberds

jurb6006@gmail.com: Dec 18 07:52PM -0800 >"OR >hoping to blame you for an inability to fix it, so *you* have to buy >the >new one. "   For that, they are going to need weapons. I mean like the government has.

"Ralph Mowery" <rmowery28146@earthlink.net>: Dec 18 11:25PM -0500 <mroberds@att.net> wrote in message news:n52ael$dqs$2@dont-email.me...   > Under a certain amount, it won't pay to spend time fixing it, unless > there are some other circumstances involved. (It was grandma's radio, > or whatever.)   That is the way I have looked at lots of things. The repair parts often cost more than the origional item. At work there was a motor and gear box of around 1/2 HP. To get a new motor or gear box actually cost within $ 5 of a whole new motor and gearbox. Then the company would have to pay the mechanic over $ 40 an hour to rebuild the unit as they were always replaced as a unit.

MJC <gravity@mjcoon.plus.com>: Dec 19 09:10AM In article <n51qfp$jqc$1@reader1.panix.com>, presence@MUNGEpanix.com says...   > They should make heated pens for writing on thermal paper.   Soldering iron?   Mike.

jurb6006@gmail.com: Dec 19 01:55AM -0800 MAKE NO PROMISES.   Ever.

Wond <gboot.phil@gmx.com>: Dec 19 04:15PM On Sat, 19 Dec 2015 01:55:44 -0800, jurb6006 wrote:   > MAKE NO PROMISES.   > Ever.   Reminds me of that fellow, Ainit da Troot

mroberds@att.net: Dec 19 12:20AM > Need recommendations of battery brand and type.   I have had good luck with both Panasonic and Power-Sonic sealed lead- acid batteries, and bad luck with everything else I've tried, including BB Battery, UB, CSB, and Power Patrol. All the Power-Sonics I bought before 2013 were made in Mexico, but the ones I bought in 2013 were made in China. I put them in my old APC UPS (circa 2000), and they're still in there now, but their longevity remains to be seen. I'd be inclined to trust a Yuasa, based on experience with their flooded batteries, but I have no experience with their sealed lead-acid batteries. I get about five or six years from these batteries in a computer UPS, where the utility power is pretty reliable. I have mostly used the "7 Ah" size (which, these days, is often labeled 7.2 or 7.5 Ah).   I usually order them online from Digi-Key or Mouser.   > Buying batteries from Amazon.   Be careful. I've checked Amazon before and a few sellers there are showing *pictures* of a Power-Sonic battery but probably *shipping* some junk battery. Caveat emptor.   Note that the "7 Ah" size can come with 3/16" wide or 1/4" wide tab terminals; make sure you get the right one. Also, I worked on an APC 1U rack-mount UPS that specified batteries with a flame-resistant casing; this was only easy to find in Panasonic's line. (They are in the Power-Sonic catalog but I couldn't figure out how to buy them in small quantities.)   Standard disclaimers apply: I don't get money or other consideration from any companies mentioned.   Matt Roberds

jurb6006@gmail.com: Dec 18 10:26AM -0800 >is not intended to nail down the exact cause of a problem, only the >most probable causes, expecting the dealer to replace things in a >rational and logical order based on their experience. "   Not even that. I think they may have been trying to rake you over the coals. As far as I know, there is no code for "catalytic convertor". the second O2 sensor is supposed to detect slightly less oxygen than the first one. This assures the cat is installed and operating. the codes them selves read something like "O2 sensor #2 reading rich", or lean. Anyone with a brain should logically replace that first. Incidentally, for this system to work, it MUST waste some fuel by making it over rich. If the mixture is stoichometric, the catalytic has nothing to do. But that is a bit easier on the valves and a few other components.   Catalytics either get clogged or burnt out. Something has to happen, prolonged driving with a misfire for example. I don't know about you, but when I drive, I want the car to run right. If it has a miss I can't stand it. If anything I can't stand it. If it burns oil I junk it. (that's why I prefer GM, seems their engines and trannies last, problem is they fell out of the damn car back in the 1980s)   You know, if the auto service business was like the consumer electronics service business, they would have pretty much had to put that cat in for free, or lied to you and put the O2 sensor in for free. Guess which. And let's not even get started about doctors, them fuckers cut off the wrong leg and expect to get paid. And that is pretty bad, because if you have one leg there ARE solutions whereby you can walk. If you have no legs that is it. I hope the guy they did that to is the richest MF sitting in the world.   But anyway, for a time I was the go to guy on hard faults in cars. (I also learned that you can CLEAN an O2 sensor) Buddy brings me his Cutlass, one of the last years you could get the bulletproof 4-151 engine. Good reliable car. Runs like shit. It REALLY REALLY acts like low fuel pressure. (a later paragraph will discuss that) Alot of cars had low fuel pressure and would start and idle, and crawl but not run. Slow fuel delivery was a big thing for a while. But that has been checked. It has also been to Mr. Goodwrench for a fifty buck diagnosis and they said to replace the engine.   They didn't know who the fuck they were talking to. They were trained to replace parts for fifty bucks an hour, we degreed cams, we had cranks machined down a thousandth or two and had them hard chromed back up to size. This is like having a forged crank, in fact better in some way. the olman had a 283 that did 9,400 RPM with a Racer Brown roller cam, ONE RPM higher it would wipe out bearing number one. They tried many things but at 9,400 RPM the laws of physics takes over and there was nothing you could do.   So anyway I drives the car up down the street, it cannot get out of its own way. Checking things out, I find the two possibilities are this crank sensor which is a bitch to change, or it jumped time. I took the air cleaner off and revved it up, and during part of the stroke it was spitting the injected gas out the top.   I said "Tear down for timing chain". (This guy was also a competent mechanic but this was a tough case) He said that they said this car does not have a timing chain, it has gears.   The next day he shows up and throws the tensioner on my kitchen table. Doesn't have a chain eh ? What kind of gears need that kind of tensioner ?   Another time my ex-lawyer had this pickup truck, I forget the make and model but it was a cheapie. It had linear torsion bar suspension, which means all the front end parameters are different. He had a tow hitch on a tow bar on the front so he could tow it with his camper. He said this is the only truck I could find that you could back up without the steering wheel whipping to a lock. It would track, and back up nicely so he wanted to keep it. Go camping and take your car with you kinda thing.   Maybe a year or so before he had the timing belt replaced. It would intermittently run like shit, not start, whatever. Nobody could figure it out.   Turns out the dodo who did the belt had lost the woodruff key and replaced it with an American version which was a bit too small. Over time it sheared, and the crank went where it wanted. Literally like 180 degrees off.   Now that is hard to detect. But we did detect it. We had to drive it too, apparently the inertia of revving and idling made it do it. Eventually we caught it, at one time the timing marks are right, and then they are wrong. W T F !   The wrong woodruff key had already mauled the crank so we brazed one in. You don't want to weld something like that in case it ever needs a front crank seal, but the brazing, and we thought about this, would stop the movement which was responsible for the failure because it just kept wearing away at it. Every compression and then power stroke moved it as this key was between the crank and the damper.   OK, that is not necessarily consumer electronics but others had looked at the thing coming up with all the wrong diagnoses. So it already had brand new plugs, module, sensors, wires, high performance lugnuts, the works.   How come some people are responsible if their diagnosis is incorrect and others are not ?

Jeff Liebermann <jeffl@cruzio.com>: Dec 18 01:59PM -0800 On Fri, 18 Dec 2015 07:49:23 -0800 (PST), "pfjw@aol.com"   >Um.... Um....   Who when where how why what?   >Have you checked the receptacle at home? And for proper polarity? >Some monitors will not function if not properly polarized. Just a thought.   I don't think that's the problem of I would have been electrocuted long ago. However, it was worth checking, especially since I did my own wiring. So I dug out my tester: <https://en.wikipedia.org/wiki/Receptacle_tester> and walked it through the maze of power strips and extension cords. Everything tests just fine.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

"Ralph Mowery" <rmowery28146@earthlink.net>: Dec 18 12:01PM -0500 <jurb6006@gmail.com> wrote in message news:decd1640-4de1-4fb8-ad9e-9ca7fa0fbf70@googlegroups.com... > dawned on me that I had reinstalled the bad part.   > Now, when I know a part is bad I do something to it. Cut off a wire of > something. Anything to distinguish it.   Done that also. Got to the point I carry a felt tip pen and mark the old one with a O or OLD on it. May just put an X or sometimes if the old part is put back in because it was not bad I put number on it.   Some of the computer controlled processes use what is called a PLC that has lots of modules about the size of the cable modems that plug into a rack. They will have a few small switches or jumpers inside them and the new one will need to be set the same as the old one. Need to keep up with which is the old part and which is the new one so the switches can be set correctly.

Tim R <timothy42b@aol.com>: Dec 18 10:55AM -0800 On Friday, December 18, 2015 at 11:58:31 AM UTC-5, Ralph Mowery wrote: > They will have a few small switches or jumpers inside them and the new one > will need to be set the same as the old one. Need to keep up with which is > the old part and which is the new one so the switches can be set correctly.   Worked at a plant that used Allen Bradley PLCs.   The program resided in memory but there was a backup EPROM in the cabinet.   You could also type it in by hand but it was thousands of lines of ladder logic, any line of which could point to any other, it would take weeks.   So we lost the program in a power surge or something. No problem, pop the EPROM in and download the program.   Meanwhile the production manager is screaming we're going to miss the ship date and lose the customer. No sense of humor, those guys.   Here's the catch: on some PLCs download the program means install it FROM the EPROM, but on these A-Bs download meant install it TO the EPROM. So we downloaded the empty program into the EPROM, erasing it.   No problem, we have a spare safely locked in the maintenance office. Notice I said A spare, as in, one. You already know what we did, popped that one in the PLC and erased that one too.

"Ralph Mowery" <rmowery28146@earthlink.net>: Dec 18 02:23PM -0500 "Tim R" <timothy42b@aol.com> wrote in message news:e779ec1c-3ca4-4ed2-ac8c-9e8a03bc6bfe@googlegroups.com...     > No problem, we have a spare safely locked in the maintenance office. > Notice I said A spare, as in, one. You already know what we did, popped > that one in the PLC and erased that one too.   We had about 40 or 50 of the AB PLC 5s in the plant. Some of the older ones. Just glad that they finally came out with some computer software that could be loaded on a laptop, and then later it was on a network where we could sit in one room and look at most of them. This I hated about the ABs were we were suspsoe to power the thing down if changing out an input or output card. When running a continious process 24/7 we did not want to shut down a PLC rack.     I liked the Fisher/Provox stuff much beter. We could hot swap any one crd at a time without shutting off the other sutff.

MJC <gravity@mjcoon.plus.com>: Dec 18 08:18PM In article <pvGdnX53DouvpunLnZ2dnUU7-eGdnZ2d@earthlink.com>, rmowery28146@earthlink.net says... > Done that also. Got to the point I carry a felt tip pen and mark the old > one with a O or OLD on it. May just put an X or sometimes if the old part > is put back in because it was not bad I put number on it.   Sounds like my late father. If the car workshop said they would replace a part he would put a small mark on the old one in situ. If the mark was still there after he was charged for a replacement he would give them hell!   Mike.

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