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"Gareth Magennis" <soundserviceleeds@outlook.com>: May 11 06:39PM +0100 "Ralph Mowery" wrote in message news:MPG.355f7305e5f630b29897c7@news.east.earthlink.net...   In article <7488be52-bc73-403a-831d-1bf7c59b2ccb@googlegroups.com>, tabbypurr@gmail.com says...   > It's the first thing I'd do. What's the first thing you'd do?   Probably the first thing I would do also.   With some of the multimeters less than $ 10 everyhone should have one and have a basic idea of how to do simple measurments.   While it would not tell if the power supply is working, it will tell if it is totally dead or maybe if the voltage is way too high or low.   An ohm check across the primary of the supply could tell if it was bad, but with the moden supplies it may not.   Some of the switching supplies may not show a voltage if not under load, but still that is where I would start.       **********************************   I read this occasionally, but I have never come across an SMPS that will not run without a load.   I have come across some that show overvoltage with no load, however.       Gareth.

jurb6006@gmail.com: May 11 11:04AM -0700 On Friday, May 11, 2018 at 12:39:58 PM UTC-5, Gareth Magennis wrote: > run without a load.   > I have come across some that show overvoltage with no load, however.   > Gareth.   If they latch into a shutdown mode from overvoltage they won't. Actually though in practice the output filter stays charged for quite some time so you have an indication that it DID run. (unless it crowbars the output)

Pat <forums@greensdomain.com>: May 11 03:35PM -0400 On Fri, 11 May 2018 18:39:53 +0100, "Gareth Magennis" >run without a load.   >I have come across some that show overvoltage with no load, however.   >Gareth.   Don't most PC power supplies stay off until that one pin is grounded on the 24 pin motherboard connector? True that isn't exactly what you were talking about, but it might give a novice the impression the supply won't start without a load becasue unplugging the load shuts down the supply.

"Gareth Magennis" <soundserviceleeds@outlook.com>: May 11 11:40PM +0100 wrote in message news:79687eab-c0c1-409c-ab32-56e088ea6caa@googlegroups.com...   On Friday, May 11, 2018 at 12:39:58 PM UTC-5, Gareth Magennis wrote: > run without a load.   > I have come across some that show overvoltage with no load, however.   > Gareth.   If they latch into a shutdown mode from overvoltage they won't. Actually though in practice the output filter stays charged for quite some time so you have an indication that it DID run. (unless it crowbars the output)       ***********************   I get that.   I still have experience of SMPS that DO produce overvoltage with no load, but are fine when connected.     Gareth.

mike <ham789@netzero.net>: May 11 06:19PM -0700 >>> junk snipped   > It's the first thing I'd do. What's the first thing you'd do?   > NT   That's the first thing I'd do too. BUT If it measured the correct voltage, I'd put a load on it and look at it with a scope. This is FAR EASIER than taking the laptop apart, only to find that the AC adapter was bad all along...and you broke a bunch of the plastic snaps trying to pry it apart. Been there, done that.   Make DARN sure the power supply is good before disassembling a laptop.   In ANY diagnostic situation, you start asking questions to determine the diagnostic tree. For each question, ask yourself, "What am I gonna do with the answer once I have it?" If you can't do anything with the answer, it doesn't help to ask the question. You can lop off whole branches of your diagnostic tree. If your lack of test equipment lops off ALL the branches, you're dead in the water. Fixing it will be a matter of luck.   In this case, if you can't load the power supply and look at it with a scope, you have two options. 1) output voltage is not correct on the multimeter.>> laptop ac supply is probably defective. 2) no load output voltage is correct...and you don't have a scope>> you probably shouldn't be taking the laptop apart until you have more info or a known-good power supply.   "my laptopl froze then made a loud buzzing sound" is NOT a good symptom That it didn't buzz next time suggests like the power supply is defective and it blew a fuse or something inside the laptop. Or that a static zap killed it when it was plugged in. OR...OR... In that case, trying a good power supply may not fix it. And if you fix the inside problem and plug in the bad supply, you may break it again. Been there done that.

Tim R <timothy42b@aol.com>: May 12 03:35AM -0700 I don't know if you have any repair resources near you.   I'll tell my story.   I had a laptop with a bad power jack. I went on youtube and watched videos on how to disassemble this brand of laptop. It's a daunting task, they aren't made to come apart easily, and that power jack is very vulnerable.   And then, before I did it, I took the laptop to Staples to their "free diagnosis" desk. They connected it to a universal power supply, one of those that comes with several connector pins. Surprise, it booted right up and charged fine.   Even though everybody I talked to was sure it was the laptop, the power supply was the actual problem. All I had to do was buy the new supply.

micky <NONONOmisc07@bigfoot.com>: May 11 08:34PM -0400 The networking ng is dormant so I thought I'd report this here.   Folded phone line can mess up DSL.     I think a couple years ago when I had 100 feet of phone line but was only using 40 feet, but wanted to save the whole 100' in one piec, I had 40 feet played out and 60 feet rolled on the spool, and I asked here or somewhere else if that could cause a slow DSL connection. And iirc the answer was no, but I'm not sure of that.   So a couple months ago I finally finish installing my home burglar alarm and I want to connect it to the monitoring company via the phone line. Since my main phone connection goes in via the second floor, to the computer on the 2nd floor, I go to the NIC and put a Y connector in it, adding back the original wire to the basement. Somewhere I have a 6" piece of phone wire with modular plugs on the end, but I can't find it, so I put in one of the cords that comes with most phone devices, maybe 8 feet folded up, maybe 6 circle's-worth, squeezed flat.   This is some time between Thursday and Saturday, and Sunday morning I leave for two months.   I got back two weeks ago today and the house and car were just the way I left them, and the computer worked fine. For 3 or 4 days. Then it stopped loading webpages, except very intermittently (so little as to be unusable), loaded email and newsgrooups only 20% or 30% of the time. People told me to call Verizon, as if I hadn't thought of that. But they charge about $60 if it's not their fault, and anyhow, the point is to figure it out on my own.   Check the NIC. It's popped open. It's under a roof but maybe it got wet. Doesn't look wet. After a couple days with no better ideas, I decide to unplug things in the NIC to give them a chance to dry, and only then I notice the folded phone cord (with the Y-connector). Take it out, and everything works fine again.   But how come it worked fine for the first 3 or 4 days I was back? And at least 12 hours, maybe 2 days, before I left?

Jason <nobody@nowhere.com>: May 11 09:41PM -0400 In article <jpccfdpqjrlaoibesg7jua0679jmd0cam3@4ax.com>, NONONOmisc07@bigfoot.com says... > I go to the NIC and put a Y connector in it,   Are there DSL isolators in line where they should be? I couldn't tell from your post.

ABLE1 <somewhere@nowhere.net>: May 11 09:46PM -0400 Micky, I am not going to answer your question as to why. Don't know. However, with you alarm system connection you need to place the alarm dialer as the first thing on your phone line from the NIC. This is done with a RJ31X block properly installed. Also, depending on your specific use of DSL Filters the line to the alarm dialer needs to be a DSL Filtered line. Otherwise the communication can be compromised. Twisted pair cable is most desirable.   Good luck.   Les     On 5/11/2018 8:34 PM, micky wrote:

Lucifer Morningstar <lucifer@gmail.com>: May 12 12:50PM +1000 On Fri, 11 May 2018 20:34:49 -0400, micky <NONONOmisc07@bigfoot.com> wrote:   >it out, and everything works fine again.   >But how come it worked fine for the first 3 or 4 days I was back? And >at least 12 hours, maybe 2 days, before I left?   On similar lines I was using a network cable that was way longer than needed and the excess was coiled up. At 1 gigabit packet loss was around 50%. I replaced it with a much shorter cable and no packet loss.

Lucifer Morningstar <lucifer@gmail.com>: May 12 12:53PM +1000 On Fri, 11 May 2018 21:46:29 -0400, ABLE1 <somewhere@nowhere.net> wrote:   >the communication can be compromised. Twisted pair cable is most desirable.   >Good luck.   >Les   https://en.wikipedia.org/wiki/Usenet_quoting

Tim <onelydad58@gmail.com>: May 12 05:30AM Lucifer Morningstar <lucifer@gmail.com> wrote in > longer than needed and the excess was coiled up. > At 1 gigabit packet loss was around 50%. > I replaced it with a much shorter cable and no packet loss.   That one is easy. Gigabit eathernet is very sensitive to interference. Having the wires coiled like that very likely degraded the line electrical characteristics to the point that you were getting a lot of lost/error packets. CAT5/CAT6 is very sensitive to proper conditions for transmission and reception. It doesn't take much to degrade a packet to the point that it is not decipherable at the other end.

Paul <nospam@needed.invalid>: May 12 02:44AM -0400 ABLE1 wrote: > desirable.   > Good luck.   > Les   Where I live, they have two practices for ADSL.   The ADSL original setup, they handed out filters per phone jack in the house. So they would put four filters in their "kit", as back then the modem was a rental. This was back in the days of "no truck roll" installs.   When ADSL2 rolled out, they started using a tiny whole-house filter, installed at the demarc. What's supposed to happen in that case, is the "existing" house phone wiring, is put on the filtered port. (And the alarm dialer could go on that network of wires.) Whereas the customer can run a cable to the ADSL (unfiltered) port on the filter, to make the ADSL2 modem work properly. The filter box was pretty small, and only 2x3 inches or so.   Paul

"Ron D." <ron.dozier@gmail.com>: May 11 02:29PM -0700 You may want to check www.tvfool.com for a list of stations that you should be able to get by your address.   www.titantv.com I use for a "TV guide". No idea about available API.   A "TSID", "Transport Stream ID" is arbitrary, but it's assigned in consecutive pairs by the FCC. A "TSID" has to be unique per geographic area, e.g tuner.   The TSID is assigned to the analog channel.   If I added my own channels via a modulator, I'd have to assign a TSID that did not already exist in my general area. This gives the "set-top-box"/tuner a way to uniquely identify a channel.   So, I think the TSID along with the minor channel number identifies a unique tuner channel. Channel 3.1 in Philadelphia and Channel 6.2 in LA would definately have a different TSID and minor channel number.   If I add modulated channels to the channels seen by the TV, I need to assign a TSID that is unique so the tuner has a unique identifier for every digital channel.

Tim R <timothy42b@aol.com>: May 11 12:51PM -0700 I found a GE clamp on amp probe at a yard sale.   It has a set of voltage probes with alligator clips, and a set of resistance probes with sharp points. Both plug into connector on the bottom.   I unscrewed the voltage probe and to my surprise there was an Eveready AA that had not leaked, though it looked this thing had been in the shed 50 years.   But it also had a fuse that was obviously blown badly. There are no markings, what would be normal for that?

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