On Monday 01 April 2019 01:09:59 John Dammeyer wrote: > Hi Gene, > > > And yes that supply s/b installed so it can be swapped out for a > > fresh one easily, the capacitors WILL die, sometimes a horribly > > messy death. Least dependable part in any system. We need to invent > > something more dependable for use as a large capacitance, but alu > > foil, kraft paper, and a cc or less of technical grade ethylene > > glycol is 100 years later, still the cheapest farad you can buy by > > several magnitudes. > > I used the highest hour rated, highest temperature and 4x the needed > value for the simple linear DC power supplies in this project. > http://www.autoartisans.com/LGB/Lions%20Gate%20Bridge%20Pano1.jpg This > summer it will have been running for 10 years without (AFAIK) any > failures. Granted the power factor sucked but a more complicated > supply that would move the PF up to close to 100% would have added a > major potential single point failure to 6 LED modules in each lamp.
Pretty impressive picture, John. Thanks. > I'm also a > > Certified Electronics Technician, now long since retired after > > spending nearly 50 years keeping some tv station on the air. > > Spent a year as a disk jockey at CJOI 1440. Evenings for the first > 2.25 hours were boring playing religious "send me your money" tapes. > After that it was rock music till 1AM. I had the job because the > automation system (International Good Music IGM) was flakey and would > play run the card reader empty and then just play the backup music > tape and no commercials. > > Since I had two hours every night where all I had to do was queue > tapes and keep the volume high enough to determine it was working I'd > play with the automation system. All RTL logic. Two of the 4 fans in > the cabinet were toast. I replaced those. (I had a high school > diploma in Electronics Technology). > > Here's how the system worked. A punched card reader. An IBM [...] It once took me around 3 years to find an engineering goofup by Chyron. They had used a cmos nand gate as an invertor, and left the 2nd input floating. Thats a CS101 lesson. When I finally found it, I called the guy whose name was on the schematic and gave him a piece of my mind that by then was decidedly spare. Another time, much earlier, I found 2 traces interchanged on a pcb in a Dynair video switcher that had a nasty habit of turningits power supply to charcoal. Schematicly it was supposed to be a foldback circuit to protect the supply from a shorted tally bulb, but the crossed traces turned the supply on full scale and let ALL the smoke out. And did it everytime a 327 bulb failed. I knew a good number of the folks at Dynair as they sponsored the annual party at the NAB for the Order of Iron Test Pattern Society, but I ragged them about it anyway. Totally tongue in cheek, as I'm a Brigadier General. > And I'm willing to bet everyone on this list running CNC can 'feel' > and 'hear' when something isn't quite right. It's so subtle and often > even difficult to explain to someone without experience. But it's > there. Yup. > > Its been quite a ride since I fixed my first tv in 1948, at 14 years > > old. Yup, I was a geek before the word was invented. But now I've > > had a couple health accidents that have slowed the thinker a bit. > > Most recently a pacemaker, I was getting dizzy in between > > heartbeats. Figured I had better get that fixed as I have a fading > > wife to care for. > > Do take care of yourself. And I'm still waiting for pictures... > <GRIN> John Somehow, I knew that was coming. :) If I ever get it working, I'll "clear the arena" and take some. Right now the bed is piled about 6" deep in tools and papers as I put the finishing but difficult touches on it. Working at my pace, often clocked by parts from China. Working on home switches and waiting for a 110 volt vfd. The one in it can't make up it mind which direction to turn the spindle, but despite its having clearly labeled FWD and REV terminals, they have no effect. I didn't want to spend the sheckles, but have anyway. Take care John. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
