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Cursitor Doom <curd@notformail.com>: Jul 14 03:40PM Hi all,   I'm having serious difficulty trying to get this issue resolved and was wondering if anyone here has come across the same problem.   I've got a linear PSU that uses a LM317 (TO-220 case) to drop 37V down to 12V for a small 555 timer board that's set up as a pulse generator (at about 0.1Hz). The thing is, as soon as I connect the board, the 12V from the reg drops to between 6V and 7V and wanders around this level (like as if I'd put a really heavy load on it). But the 555 board's resistance is about 22k ohms so it only needs a very small current. When I swap the board for a 10W 50 ohm power resistor drawing 0.25A, the reg output is totally fine, staying rock steady at 12V and the resistor and reg get warm as you would expect. I can only think there may be something about the timer board that 'upsets' the LM317 and causes it to incorrectly partially shutdown, because nothing on the board is getting warm and trying spare identical timer boards causes the voltage to drop by the same amount also.   I can't recall this ever happening before! Any suggestions? TIA.

Ralph Mowery <rmowery28146@earthlink.net>: Jul 14 11:49AM -0400 In article <nm8bok$rig$1@dont-email.me>, curd@notformail.com says... > timer boards causes the voltage to drop by the same amount also.   > I can't recall this ever happening before! Any suggestions? > TIA.   Try loading it down some. The data sheet calls from about 3 to 10 ma as the minimum load.     --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jul 14 11:53AM -0400 On 07/14/2016 11:40 AM, Cursitor Doom wrote: > timer boards causes the voltage to drop by the same amount also.   > I can't recall this ever happening before! Any suggestions? > TIA.   Too small an output cap, or too low an ESR? Three terminal regulators can oscillate. Try hanging 100 uF aluminum electro on the output and see if it starts behaving better.     Cheers   Phil Hobbs     -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jul 14 11:54AM -0400 On 07/14/2016 11:49 AM, Ralph Mowery wrote: >> TIA.   > Try loading it down some. The data sheet calls from about 3 to 10 ma as > the minimum load.   Too light a load causes the output voltage to go too high, though.   Cheers   Phil Hobbs     -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

Cursitor Doom <curd@notformail.com>: Jul 14 05:12PM On Thu, 14 Jul 2016 11:53:30 -0400, Phil Hobbs wrote:   > Too small an output cap, or too low an ESR? Three terminal regulators > can oscillate. Try hanging 100 uF aluminum electro on the output and > see if it starts behaving better.   The datasheet says output caps are "optional" although I do always use 'em. The one I'd fitted was 1nF which seemed a bit small, so I subbed it for a 100n but it's made no difference. 100uF seems HUGE! I might try it, though.

Cursitor Doom <curd@notformail.com>: Jul 14 05:13PM On Thu, 14 Jul 2016 11:49:42 -0400, Ralph Mowery wrote:   > Try loading it down some. The data sheet calls from about 3 to 10 ma as > the minimum load.   Tried it before posting but no joy, I'm afraid.

Bob Engelhardt <BobEngelhardt@comcast.net>: Jul 14 01:29PM -0400 On 7/14/2016 11:40 AM, Cursitor Doom wrote: >... But the 555 board's resistance is > about 22k ohms so it only needs a very small current. ...   Can you measure what the board is actually drawing?

Jeff Liebermann <jeffl@cruzio.com>: Jul 14 10:35AM -0700 On Thu, 14 Jul 2016 15:40:04 -0000 (UTC), Cursitor Doom   >I've got a linear PSU that uses a LM317 (TO-220 case) to drop 37V down to >12V for a small 555 timer board that's set up as a pulse generator (at >about 0.1Hz).   The data sheet at: <http://www.ti.com/lit/ds/symlink/lm317.pdf> says that 37V is the maximum output voltage with an input-output voltage difference of 40V absolute max. With 37v in and 12v out, you're within spec, but seems to me too close for comfort. Maybe you blew up the LM317? Try another LM317 and watch your input voltage carefully. Or maybe add a big dropping resistor between your 37v supply and the LM317 input.       -- 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

Lee <cyberwitch@ukonline.net>: Jul 14 06:40PM +0100 On 14/07/2016 18:12, Cursitor Doom wrote: > 'em. The one I'd fitted was 1nF which seemed a bit small, so I subbed it > for a 100n but it's made no difference. 100uF seems HUGE! I might try it, > though.   JOOI What version of the 555? If it's a bipolar version they can exhibit a "crowbar effect", and the 100uf cap is usually suggested to ameliorate it.

Cursitor Doom <curd@notformail.com>: Jul 14 06:40PM On Thu, 14 Jul 2016 18:40:16 +0100, Lee wrote:   > JOOI What version of the 555? If it's a bipolar version they can exhibit > a "crowbar effect", and the 100uf cap is usually suggested to > ameliorate it.   The ones I'm using here are all NE555CN.

Cursitor Doom <curd@notformail.com>: Jul 14 06:45PM On Thu, 14 Jul 2016 13:29:38 -0400, Bob Engelhardt wrote:   >>... But the 555 board's resistance is >> about 22k ohms so it only needs a very small current. ...   > Can you measure what the board is actually drawing?   When connected to an external bench power supply at 12V., the board draws 9.3mA. The bench PSU doesn't have any issues powering this board.   When connected to PSU that uses the LM317, however, it draws 3mA and the voltage across it drops to around 6V.

Cursitor Doom <curd@notformail.com>: Jul 14 06:47PM On Thu, 14 Jul 2016 10:35:32 -0700, Jeff Liebermann wrote:   > Maybe you blew up the > LM317?   Don't see how that's possible, Jeff, since it's still happy to supply passive loads that are much heavier, and at a rock solid stable output voltage.

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jul 14 03:50PM -0400 On 07/14/2016 01:12 PM, Cursitor Doom wrote: > 'em. The one I'd fitted was 1nF which seemed a bit small, so I subbed it > for a 100n but it's made no difference. 100uF seems HUGE! I might try it, > though.   100nF is guaranteed to make a 317 oscillate. Microfarads, me lad, microfarads.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

jeanyves <jeanyves@nowhere.com>: Jul 14 09:49PM +0200 On 2016-07-13 22:10:02 +0000, Amanda Riphnykhazova said:   > Thanks guys: The LED vendors (in China) all tout their MR16s as being > direct replacements for the MR16 12v halogens   be aware that the light beam can be very different from a 12v halogen bulb ... prefer led lamps that are made of smd leds, they have a wider light beam the lamps that have 3x 1W led have a very directive beam and will really not shine like your halogen lights.   I also had halogen lights long ago, and replaced with led some years ago. when I inspect the wires for changing the lights, I noticed that the original wires where cooked by the heat of the pravious lights... 12v and 20w or even 50w make the wires really be cooked.   I replaced the wires, and used then GU10 led lamps, and now the current flowing into the wires is lower than before.   --   Jean-Yves.

etpm@whidbey.com: Jul 14 12:10PM -0700 I have a computer with a funky power supply. It won't turn on until something in it is warm enough. I have ordered another but a new problem has cropped up in this computer. The monitor said there was no signal even though it was connected to the computer. Thinking it might be dirty contacts I removed the video card and the monitor cable, cleaned the contacts, and plugged everything back in. No joy. I unplugged the computer and let it sit about an hour. Plugged it back in, tried turning it on but had to wait a few minutes for the power supply to start fully functioning and when it did the computer worked properly and the monitor had a picture. I left the computer on for several days and everything worked fine until this morning when once again the monitor reported no signal and once again no picture. So I removed power from the computer and removed the video card. I put the card in the fridge for abou 1/2 hour. Then I put the card back in the computer, plugged the computer back in, waited the few minutes again, and now it all works fine again. So, should I start shopping for a video card too? Could the flaky power supply be affecting the video card too? Eric

Stormin Mormon <cayoung61@hotmail.com>: Jul 13 07:42PM -0400 On 7/13/2016 1:09 PM, Danny D. wrote:   > The 1/2-to-1/3HP hard-start cap isn't working.   > Half the time it starts the compressor, and half the time it does NOT start > the compressor.   Yes, it's obvious that you don't see.     -- . Christopher A. Young learn more about Jesus . www.lds.org . .

Hugh Jass <hugh@anonym.ous>: Jul 13 08:05PM -0400 On 7/13/2016 1:09 PM, Danny D. wrote: > I'm trying to fix the frig while keeping my sister from saying "I told you > so" and while my wife is constantly asking me when she can have her kitchen > back.   Just tell them if they had a penis, they could actually be useful and help.

"Danny D." <dannydiamico@yahoo.com>: Jul 14 01:52AM On Wed, 13 Jul 2016 12:50:44 -0700, Oren wrote:   > He gets mad if your thread count is higher than his.   > And he doesn't know you are a bean counter accountant with size 11.5 > sneakers.   You know me better'n my mother does!   :)

"Danny D." <dannydiamico@yahoo.com>: Jul 14 02:00AM On Wed, 13 Jul 2016 19:42:21 -0400, Stormin Mormon wrote:   > Yes, it's obvious that you don't see.   Here's the thing. I'm obviously not an engineer nor a tech. I'm just a guy.   I had never looked at the back of a frig in my life before. I ask you guys for help because the frig is a riddle to me. I don't need more riddles though.   I tried cleaning the condenser coils with a flexible brush, but that's basically impossible (to get to the other half). http://i.cubeupload.com/rYcpn0.jpg   So I cleaned the coils by blowing with an airgun at 100psi or so: http://i.cubeupload.com/q1fSgx.jpg   That left a trail of dust devils in the kitchen: http://i.cubeupload.com/Vvbex9.jpg   And then I hooked the hard-start capacitor to refrigerator power: http://i.cubeupload.com/62T0dG.jpg   Since that didn't help, I tried hooking the hard-start cap to its own separate power: http://i.cubeupload.com/VsCyzM.jpg   I can plug and unplug at will (letting it rest a half hour between): http://i.cubeupload.com/Dio9Uz.jpg   It only starts sometimes.   The rest of the time it's just pulling 13.5 Amps and not starting: http://i.cubeupload.com/Wo2RvQ.jpg

"Danny D." <dannydiamico@yahoo.com>: Jul 14 02:08AM On Wed, 13 Jul 2016 14:19:30 -0400, FrozenNorth wrote:   > Good Lord, replace the cap, they are not that expensive, otherwise buy a > new fridge, that costs more money. If the light comes on inside when > you open the door the power works, why look beyond that?   Hmmm... I'm confused.   The cap "is" replaced. It's replaced by the 3in1 unit.   Or do I misunderstand the advice?

"Danny D." <dannydiamico@yahoo.com>: Jul 14 02:09AM On Wed, 13 Jul 2016 21:47:59 +0100, Mike Tomlinson wrote:   > you need help from a mental health professional   :)

Stormin Mormon <cayoung61@hotmail.com>: Jul 13 07:56AM -0400 On 7/13/2016 12:56 AM, Danny D. wrote:   > Is it OK to have the frig temporarily on two power cords? > a. One for the fan and the rest of the frig > b. One just for the compressor   If you'd done what I said, and played along, this could have been fixed last week. Hope you are enjoying your self.   -- . Christopher A. Young learn more about Jesus . www.lds.org . .

Stormin Mormon <cayoung61@hotmail.com>: Jul 14 08:44AM -0400 On 7/13/2016 10:00 PM, Danny D. wrote:   > I had never looked at the back of a frig in my life before. > I ask you guys for help because the frig is a riddle to me. > I don't need more riddles though.   When you run into a problem, you can either do things differently, or force harder, using the technique which has failed up to that point.   I offered you (repeatedly) a chance to do differently, and you ignored me repeatedly. This post is an example of trying to force your failing techniques even harder, and trying to force me to participate with your failings. I'll have you know, that I viewed NONE of the links, and barely read your text.   By way of references, I've been working on domstic refrigerators for over 10 years. I'm fairly sure that if you'd done what I said, it would have been fixed several days ago. I'm also fairly sure I know why your compressor keeps going off.   -- . Christopher A. Young learn more about Jesus . www.lds.org . .

"pfjw@aol.com" <pfjw@aol.com>: Jul 14 06:30AM -0700 On Thursday, July 14, 2016 at 8:44:31 AM UTC-4, Stormin Mormon wrote:

"pfjw@aol.com" <pfjw@aol.com>: Jul 14 06:33AM -0700 > > When you run into a problem, you can either > > do things differently, or force harder, using > > the technique which has failed up to that point.   The definition of insanity is to do the same thing over and over, expecting different results.   Peter Wieck Melrose Park, PA

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