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"NY" <me@privacy.net>: Apr 09 03:14PM +0100 <krw@notreal.com> wrote in message news:g0akec5be84fpoh2a0dukvh2613de8i570@4ax.com... > emergency generators once a month. I have no idea why they had such > in the building I was in (just offices and a few labs at that time) > but they were there, so the were tested.   The office building where I worked had huge diesel-powered generator to cope with power cuts. My office was near it, and I know it wasn't tested during office hours for five years. One day there was a power cut that affected the whole town, and the diesel engine fired up, amid a tremendous roar and lots of filthy black smoke. Power returned for about a minute and then there was a huge explosion and a jet of flames. Apparently the generator couldn't handle the load, even with the engine working as hard as it could (a good diesel grunt!) and something caught fire, igniting the diesel tank. Turned out that it had been specced back in the days when there wasn't a PC on every single person's desk, and it was woefully underpowered for the modern demands that were placed on it.

krw@notreal.com: Apr 08 10:05PM -0400 On Sat, 8 Apr 2017 20:17:20 +0100, "Benderthe.evilrobot"   >You can't just lump everything into the same bracket - a lot of people just >turn the TV off "cold turkey", its a lot better than leaving it unattended >on standby.   There is absolutly nothing wrong with "standby".   >Anything with a hard drive can trash a file if you power down in the middle >of a write operation.   Nonsense. There are many ways to design a device that will survive a power failure during disk write. A bit of reserve power is probably the best solution but a JFS works, too. >caps discharge and those with inrush surge limiting have a thermal recovery >time for no protection - but it just stresses the components a little more >than usual. Most user manuals seem more or less unanimous for about 30s.   Only if it's designed by a moron.

oldschool@tubes.com: Apr 08 07:33PM -0400 On Sat, 8 Apr 2017 20:17:20 +0100, "Benderthe.evilrobot" >time for no protection - but it just stresses the components a little more >than usual. Most user manuals seem more or less unanimous for about 30s.   >---   I have a small low powered solid state stereo receiver. I noticed that things is always using power when it's turned off. A few weeks ago, while this receiver was OFF, I removed the speaker wires to test another amp. I then unplugged the receiver. Last week I put the speaker wires back on that receiver (it was still unplugged). There was a loud pop on each channel when I put the wires on it. (That was around 16 days later). Those caps must hold power for a real long time..... (There is no battery of any sort in this thing).   Another thing, I have an external 56K modem that I use to connect (on dialup). Once and awhile if I shut off connection, later on, I have trouble connecting to the internet. I found that if I just shut the power off to that modem, it seems to reset it and thn it connects fine. BUT. I have to shut it off for about 30 seconds. Just ON-OFF dont work. I assume the caps need to discharge to do the reset....

N_Cook <diverse@tcp.co.uk>: Apr 14 02:50PM +0100 Hybrid valve prea and S/S pa. Intemittant early PbF faults but also sometimes ch2 had no signal throughput when selected. ch2 Amp would work when not fully refitted in case as though a grounding problem, but wrong way round, would work when pots not connected to chassis. Awkward because the errant pot has closed contacts to ground of unpowered relay across it. Eventually realised 15R , not 0R and that 15R was to the shaft of the pot , when the pcb and pot was fully free of the chassis. Alpha pot with the back casing slightly bent-in slightly rather than out,if anything, at the slot or termination side of the pot and just about touching the pot track at the "0" end .

John Robertson <spam@flippers.com>: Apr 09 03:24PM -0700 > assuming you are in the USA) ship stuff to us by US Post as the import > fees (if that happens) is around $7US. "   > What happened to NAFTA ? Is that only for stuff coming into the US ?   Nothing to do with NAFTA. There is no duty, however the couriers still charge $25 to $45 Customs Clearance Fee for carrying the stuff across the border into Canada. Large companies like Digi-Key deal with this sort of thing differently, but for smaller businesses and individuals that clearance fee can be an unfriendly reminder that the Post Office is the best deal for shipping internationally.   We don't ship al lot to the US by courier, mostly Post and I haven't heard back from our US customers that they have been charged clearance fees for getting their products. Even the few packages that go by Fedex seem to enter the US without a fee.   Grumble.   John :-#(#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

pamela <invalid@nospam.com>: Apr 08 10:33AM +0100 As a rule of thumb, what's the shortest period to switch off electronic equipment for a reset before switching on?   I mean equipment like televisions, PVR, satellite or cable boxes, PCs, cordless phones, clock radios, etc.   My teenage relative reset our Humax PVR by switching it off and almost INSTANTLY switched it on again. I told him to be patient but how long should he wait for in general?   Twenty years ago 5 seconds would have been enough but nowadays some electronic devices (like my Samsung tv) shows its power LED for 10 or 20 seconds after the mains is disconnected. Also hard drives in Playstations and PVRs will spin on. Telling impatient kids to go and make a cup of coffee isn't going to work.

pamela <invalid@nospam.com>: Apr 08 12:37PM +0100 On 12:11 8 Apr 2017, Davey wrote:   > so I have no idea what the problem was. The unit is now about 4 > years old, and was a refurbished unit when I got it, so I have > had my money's worth if it failed at any time.   To my young relative 30 seconds is like an eternity. If I advised him to wait 30 seconds before turning equipment back on again, he would never manage it.   However his OFF-ON is so quick that it makes me think on some occassions he could create a power surge.

Mike Paff <paffm@yahoo.com>: Apr 13 03:34PM -0700 On Thu, 13 Apr 2017 22:16:58 -0000 (UTC), Cursitor Doom >never admit it in a newsgroup! >I still think the best combo by far is Scandanavian amps like B&O coupled >with English speakers such as Celestion, Tannoy, KEF & so forth. YMMV.   HK in this case refers to Harmon Kardon, not Hong Kong.

bitrex <bitrex@de.lete.earthlink.net>: Apr 14 11:38AM -0400 > The only pacific rim audio equipment I use are CD changers from Sony, Japan. The rest is US or Euro in origin.   > Peter Wieck > Melrose Park, PA   I used to have an Onkyo TX-2500 mk2 receiver from around 1978; I thought it was pretty nice! for being a "low-end" Japanese receiver from that era. Got lost in a move I think, wish I knew what happened to it...   <https://s-media-cache-ak0.pinimg.com/originals/d8/cd/9e/d8cd9e5b5eac265995e40cfd6bff35d0.jpg>

Cursitor Doom <curd@notformail.com>: Apr 13 10:16PM > 19). Again I can (and do) run *LOUD* and have never, repeat, never > damaged a speaker thereby. This is not to mention the several other amp > & speaker combinations in the inventory.   God that must sound terrible. I would never even contemplate buying amps made in Hong Kong (or mainland China for that matter). And I'd certainly never admit it in a newsgroup! I still think the best combo by far is Scandanavian amps like B&O coupled with English speakers such as Celestion, Tannoy, KEF & so forth. YMMV.

"David Farber" <farberbear.unspam@aol.com>: Apr 14 10:29AM -0700 Phil Allison wrote:   > The OP got himself a proper watt meter a posted the correct numbers.   > Drop dead ASAP you psycho, old pig.   > .... Phil   Hi Friends,   I received the new drain pump and tested it first. It seemed to wobble a bit as it began to spin up, but once it reached full speed, it was very smooth. The power meter read 13 watts. I put a little pressure on the front of the impeller and it did not slow down at all. I installed it and all is good again.   I then disassembled the old pump just to have a look inside. I was expecting it would not come apart very easily. I was wrong. I put two screwdrivers on opposite sides of the impeller, used them as levers, and it popped right out. Here is a photo of the old pump. http://webpages.charter.net/mrfixiter/images/Whirlpool/Drain-pump.jpg   Thanks for all your help. -- David Farber Los Osos, CA

lometon592@gmail.com: Apr 16 03:33PM -0700 Mine does that too. I just set the fan speed to 4 so it doesn't overheat

Adrian Caspersz <email@here.invalid>: Apr 17 09:34AM +0100 > Mine does that too. I just set the fan speed to 4 so it doesn't overheat   Responding to a 17yr old post.       Nothing to see here, move along ....   -- Adrian C

Tomos Davies <cariadmenywod@gmail.com>: Apr 11 10:37PM Given that you can have manufacturers' red and yellow match mounting balancing dots can occur at any location on the tire sidewall, which, theoretically, is the "most balanced" tire (out of the box) when chosen out of a large selection of tires? a. When the red and yellow dots are at or near the same location b. When the red and yellow dots are about 180 degrees apart c. When the red and yellow dots are about 90 degrees apart   We all know that the yellow dot is usually the tire light spot (to be matched with the wheel heavy spot which is almost always the valve) and that the red spot is generally the tire out-of-round (aka radial runout & radial force variation) sidewall-thickness spot (which also is to be mounted at the tire valve in most cases).   While the red dot wins (if both dots exist) unless the wheel is so new that the match-mounting marks are still visible (and accurate), the question I ask has never been asked by anyone to my knowledge.   The reason this question has never been asked is probably because it's an engineering question, mostly theoretical, since you can mount the tire any way you want and still balance it just fine with the proper equipment.   So I ask the THEORETICAL question only to learn more about tires.   Given that you can have manufacturers' red and yellow match mounting balancing dots can be found at any location on the tire sidewall, which, theoretically, is the "most balanced" tire (out of the box) when chosen out of a large selection of tires? a. When the red and yellow dots are at or near the same location b. When the red and yellow dots are about 180 degrees apart c. When the red and yellow dots are about 90 degrees apart

legg <legg@nospam.magma.ca>: Apr 13 07:40AM -0400 Kook number one says to kook number two, "Don't press that button".   RL

etpm@whidbey.com: Apr 11 05:17PM -0700 I'm sure someone here can help. I need to get power to a solenoid operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts. The power will be on for about 4 seconds and off for 7 seconds. This on/off cycle will be going on 10 hours a day. I have looked at slip rings online but the high speed through hole type are really spendy. Then I got to thinking about the slip rings in alternator. They certainly can carry enough current but I don't know how fast alternators typically spin. I do have an old alternator that would make a good slip ring donor. Anybody know or have a better idea? I need about 1 inch diameter through the slip rings. Thanks, Eric

Rheilly Phoull <rheilly@bigslong.com>: Apr 12 09:11AM +0800 > need about 1 inch diameter through the slip rings. > Thanks, > Eric   Not sure which "alternator" you have but a U/S vehicle one would yield what you want most likely, probably you could mod the brush holders too.

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Apr 12 08:26PM +0100 <etpm@whidbey.com> wrote in message news:fdsqec5rf15rsplc1nnb6hjndj3gu4bju2@4ax.com... > need about 1 inch diameter through the slip rings. > Thanks, > Eric   Most motorcycle alternators deliver peak output at 5000RPM - they're probably not all that different to car ones.   AFAIK: most car alternators moved on to coaxial pole coupling for the rotary field winding - which eliminates the need for slip rings.     --- This email has been checked for viruses by AVG. http://www.avg.com

Cursitor Doom <curd@notformail.com>: Apr 11 09:28PM Hi all,   I finally got around to taking a look at our tumble dryer, which has been out of action for a while (SWMBO's nagging finally paid off for her). In order to get it spinning round, you have to give the drum an initial shove, after which it rotates totally fine. But it cannot revolve without that artificial boost at start-up. I don't deal with repairing this kind of gear, but still fixed it within 5 minutes anyway. The 7uF/400V cap that lies strapped to the motor was faulty (had gone completely open-circuit). It was the first thing I checked. Nevertheless, I'm still unsure what exactly this cap's purpose is. AIR, they are often referred to as 'motor-start caps' or 'motor-run caps' but why are they needed? I'm guessing if they weren't used then manufacturers would have to fit more powerful motors simply to overcome the start-up inertia and a cap is cheaper than a heftier motor. But that's just a guess. Can some kind soul disabuse me of my ignorance here, please?

Foxs Mercantile <jdangus@att.net>: Apr 11 04:55PM -0500 On 4/11/2017 4:28 PM, Cursitor Doom wrote: > Nevertheless, I'm still unsure what exactly this cap's purpose is. > AIR, they are often referred to as 'motor-start caps' or 'motor-run > caps' but why are they needed?   Typical motors don't have to torque to start turning on their own. The start winding in series with the start capacitor provides the torque to start the motor. There's a switch to disconnect the capacitor after the motor comes up to speed.       -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

etpm@whidbey.com: Apr 11 04:11PM -0700 On Tue, 11 Apr 2017 21:28:41 -0000 (UTC), Cursitor Doom >would have to fit more powerful motors simply to overcome the start-up >inertia and a cap is cheaper than a heftier motor. But that's just a >guess. Can some kind soul disabuse me of my ignorance here, please? A single phase induction motor won't spin up without a push. This is because until the motor is spinning there is no ratating magnetic field. There are many ways to do this. One way is to use a starting capacitor. This cap is connected to a different winding, called the start winding, than the run winding and causes a phase shift, about 90 electrical degrees to the run winding. This gives the rotor a direction to start spinning. There is a centrifugal switch that takes the cap out of the circuit once the motor is about 85% of rated speed. If left in circuit the start winding would overheat. Another cap scheme is to have a cap that starts the motor and stays in circuit. This scheme doesn't provide as much starting torque but does have the advantage of simplicity and making the motor run smoother. There are also motors with switched start caps and always in circuit run caps. Eric

Rheilly Phoull <rheilly@bigslong.com>: Apr 12 09:15AM +0800 > advantage of simplicity and making the motor run smoother. There are > also motors with switched start caps and always in circuit run caps. > Eric   Most dryers I've seen have a "Run" cap only. I.e it stays in circuit all the time, much smaller rating than a "Start" cap and typically 7uF.

mike <ham789@netzero.net>: Apr 11 09:23PM -0700 On 4/11/2017 4:24 PM, Cursitor Doom wrote: > there' as I would like (and these prods don't have the removable > shrouds). So it'll have to wait til tomorrow when I can get some more > suitable ones. :(   Take the socket from a PC power supply IDE disk power connector without the plastic part. Solder a short piece of piano wire to one of the connector sockets. Fits nicely over typical DVM probes and can fit into small places for probing battery sockets.

Cursitor Doom <curd@notformail.com>: Apr 11 11:24PM On Tue, 11 Apr 2017 23:37:29 +0100, Gareth Magennis wrote:   > You are not checking from "head to toe".   > You might think you are, but you are not.   You were right! However there's still something not right about the continuity of the battery caddy. Unfortunately I can't go any further tonight partially due to the stupid modern prods you get with the absurd amount of shrouding which is making it impossible for me to 'get right in there' as I would like (and these prods don't have the removable shrouds). So it'll have to wait til tomorrow when I can get some more suitable ones. :(

Cursitor Doom <curd@notformail.com>: Apr 11 10:03PM Hi all,   Earlier I needed to do something with my graphing calculator. It only gets used very rarely so I wasn't surprised when it didn't switch on. I immediately suspected the batteries, but they were fine. All the same, I slipped in a brand new set. Still nothing. In the battery compartment they have an arrangement of 4xAAA cells in series to give a 6V supply. However, on checking the voltage from 'head to toe' as it were (from the first '-' to the last '+') I got a reading of minus 3V instead of the plus 6V I'd expected. Checked all the connections and the probes in the right sockets and whatnot: all fine. I'm sure I've had this issue before with a different battery appliance in the dim and distant past but can't recall what the cause was. It's like it's too far in the back of my mind to resurrect any more. :( Can anyone assist, please?

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