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gregz <zekor@comcast.net>: Apr 25 08:19AM > had bad experience with battery chargers.   > Thanks   > i   I have some good ones, until they broke. Some lead acid chargers I built with 80s. Chip, with temp sensing. Don't know if any still work. My trusty 4 amp manual charger for lead acid still working after 35 years. I got an old Eico variable variac battery eliminator is nice to use manually.   Greg

Roger Blake <rogblake@iname.invalid>: Apr 25 12:59PM > My experience with them has been generally negative. The worst are the > so called "smart" chargers.   My best experiences have been with old-school "dumb" chargers. I have a 4-amp model purchased over 40 years that is still going strong, works every time. Recently I purchased a modern charger but it would not work worth a damn even after returning for a replacement. So I went back to the old standby and picked up another similar charger at a flea market. That one also works great.   "New" and "improved" are not always the same thing.   -- ----------------------------------------------------------------------------- Roger Blake (Posts from Google Groups killfiled due to excess spam.)   NSA sedition and treason -- http://www.DeathToNSAthugs.com -----------------------------------------------------------------------------

avagadro7@gmail.com: Apr 25 06:07AM -0700 using Ctek with Optima batts...one Ctek-one Optima...excellent results...super super...   have a simpler n less expensive device from Powerstream for 6V.   tried rechargeable AA batts.....shoot on site.

Cydrome Leader <presence@MUNGEpanix.com>: Apr 25 04:07PM > off, if they simply tried to maintain 13.3 volts or some such.   > My question is, is my experience unique and atypical, or have you also > had bad experience with battery chargers.   It's pretty safe to say most chargers are just stupid, but lots of batteries are also garbage, and neither can compensate for each other in the end.   Apparently the last batteries installed in the UPS at work were total pieces of garbage and are dying off before 5 years. They're larger than car battery sized so should last quite some time.   The testing company comes in and does an ESR test on each battery, which shows faults the charger (it's a 545 volt system) won't ever detect.   The charts for each battery are pretty cool, (sorry, I can't share them). I can note that one problem battery is about 250mV lower than the rest and has an ESR of 65,000 microhms vs an average of 15,000 for the rest. One year ago the bad battery had voltage of 14.00 which is high, so the failure wasn't sudden and the weird data shows up on various charts.   They've removed the funky battery from the battery string and then dropped the charger voltage in the UPS to prevent damage to the rest of the batteries.   Basically, if this battery which might explode under real use was attached to a 12V float charger all that would happen is more electroylte would just boil out, it would never finish charging and it wouldn't work right anyways. The charger would have no idea anything was even wrong without past performance data or known good specs for the battery being inputted anyways.   Batteries are can have complex failure modes that you just won't catch with a volt meter. It looks like full load on these batteries is about 150Amps, so it's any hot spots would get get really interesting buring a power failure.

Danny DiAmico <dannydiamico@yahoo.com>: Apr 25 03:01PM On Mon, 25 Apr 2016 04:49:33 -0700, Uncle Monster wrote:   > it has swelled or is leaking. Here's a video of a fellow replacing some > failed electrolytic capacitors in a TV set. This will give you some idea > of what to look for on your washer's control board or power supply. ^_^     There was absolutely no smell, although we used to blow up electrolytic caps (the blue unipolar water tank type) by sticking them in outlets in physics class and then waiting for some unsuspecting student to turn the lights on in the Physics lab - and I don't remember any smell at that time.   Anyway, the wife screamed when it happened, so I was there within a minute, and I didn't detect any smell myself.   I'm very familiar with the electrolytic caps, and I am hopeful that I'll see something burnt or blown inside when I open it up.

"pfjw@aol.com" <pfjw@aol.com>: Apr 25 07:57AM -0700 Apples and oranges. The woman was Asian. Bulgaria is a small eastern European nation not known for its technical prowess. Only a pinfeather reactionary would confuse the issue and attempt to mix a metaphor based on that confusion.   We have switches, but a smart thermostat with an outside air sensor. The boiler will vary output water temperature as well, making for very steady interior temperatures in cold weather. Basic feedback devices, nothing much special.   Peter Wieck Melrose Park, PA

N_Cook <diverse@tcp.co.uk>: Apr 25 03:48PM +0100 It seems the plastic housing has deformed to slightly oval tubes or something, but no rechargeable AA size batteries (2x2) comfortably slide in and out. Had to cut in from the side to make an access point to lever out the 2 deeper AAs, wedged in ther, no corrossion , just lack of freeboard. Any ideas how to enlarge the bores a bit, no engineering reamer available. Those silly sandpaper cylinders on a rubber cylinder "mandrel" for "Dremmels" would do the job if there was a way to extend the shaft. I'll try the core of a "choc block" connector as a coupler, but any other ideas?

N_Cook <diverse@tcp.co.uk>: Apr 25 03:40PM +0100 Failed backlighting. Firstly 2 off 8pin SOIC with 4 pins commoned for heatsinking, to drive backlight Tx, on the mains SMPS LV side. Markings look like PRAAN FOS 8862C under 30x microscope, google comes up with nothing, anyone suggest likely mistrancription alphanumerics?   DVD plays and sound emerges, not tried a torch on LCD as all a lash-up at the moment. That Tx powers 2 separate tubes with only 2 3KV caps the other components, 1 of 3.9pF and other 4.7pF , different size tubes likely?. Both separate secondaries of that Tx measure 830 ohm each 500V Insulation testing showed >200M for each of those 3KV caps. Not knowmingly have any puffy 3KV caps around and tried 2 x 27pF 12KV ones instead. The whole unit went into a protection mode it seems, no DVD or sound. Replaced the original 3KV caps and back to the previous situation. Does this suggest the 2 drivers are working, they cold test DVM-D pin to pin combinations matching across each ? Unplugging each lamp in turn makes no difference. Only the second time I've peered into backlight operation , so somewhat unknown territory, previous time was leaky HV caps.

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