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Jonas Schneider <Jonas123Schneider@arcor.de>: Feb 26 12:32AM Today I tried to hook up a Rocket M2 as a super powerful (miles) Wi-Fi extension for my home router, when the POE light went out whenever I plugged in the power cable. Huh?   Turns out it's a crossover cable, mixed up with the bunch of my other spare Ethernet cables.   Do we even need crossover cables anymore? Or did they go the way of 8-track players?

FrozenNorth <frozennorth.ask@gmail.com>: Feb 25 07:45PM -0500 On 2017-02-25 7:32 PM, Jonas Schneider wrote: > Ethernet cables.   > Do we even need crossover cables anymore? > Or did they go the way of 8-track players?   Most devices do not need cross over cables anymore, but there may still be the odd one floating around out there.   -- Froz....

Joe Chisolm <jchisolm6@earthlink.net>: Feb 24 09:54AM -0600 On Tue, 21 Feb 2017 10:03:40 -0600, Joe Chisolm wrote:   > to check availability, price and shipping cost. It also depends on > where you live. I'm 4 hours driving distance from Mouser so normal > UPS ground is "next day" for me.   I got a email yesterday that Newark is doing $5 shipping on orders < $49 and free shipping on orders $49 and over. Cavaet is parts must be in a USA warehouse and shipping to a USA address.     -- Chisolm Republic of Texas

Jon Elson <jmelson@wustl.edu>: Feb 21 02:15PM -0600 > What is the best place for a hobbiest to buy small amounts of electronic > parts?   I buy a lot of stuff from Digi-Key. They do have a minimum order, but it is not that bad. These days, if you buy a few chips as well as passives, you are pretty likely to go above their minimum (I think it is still $25). Their single-piece prices are not really steep.   Mouser is also pretty good.   Jon

Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat>: Feb 23 11:24PM -0500 On Thu, 23 Feb 2017 13:49:23 -0500, the renowned rickman >Vietnam and a cyclist was hit. The two drivers started haggling and >bystanders joined in to mediate. In the end it was decided that the >cyclist should get $50. They said my friend should pay.   Yes, typical Asian logic and I'm all too familiar with it- if the foreign devil wasn't there the taxi wouldn't have been carrying him, and thus the cyclist wouldn't have been hit.   You can see a smidgeon of that in some of the anti-immigrant rhetoric on this side of the pond.   --sp     -- Best regards, Spehro Pefhany

Steve Kraus <screen@SPAMBLOCKfilmteknik.com>: Feb 23 09:55PM -0600 I just had an idea. I have a UPS sitting around out of service as the batteries went dead and even with good batteries I don't know how long it would run even at very low load. I don't know how precise it is though when I looked at it on a scope it was a nice sine wave and looked stable in frequency compared to the mains. I could rig a 24VDC supply and use the output of the UPS to run my group of timers that I am testing. If the UPS has an accurate output then the timers should be accurate as well. If the UPS is fast or slow then at least the timers will get ahead or behind the same amount each day, not varying like I have observed. Hopefully it would be stable at whatever frequency it is and not go up and down.     Jeroni Paul wrote:

oldschool@tubes.com: Feb 25 08:25PM -0600 I ordered a small amplifier board on ebay. It's just a PCB with components, making a ready to go low powered audio amplifier, complete with a volume control.   It has three screw terminal blocks to attach the Power, Input and Output. It also has a 1/8" jack.   But here is the problem. Those screw blocks are labelled in Chinese. Using the actual chinese alphabet. If it was another language, I could convert the words online, but I cant enter chinese characters.   Fortunately, the power one says 12v with a + on one side, so I know that is the 12v source. But I hav no clue which of the other two are input or output, nor what that 1/8" plug is for.   I bought this from a US seller. You would think he would include a piece of paper showing what is what. The entire amp is mostly just one IC chip. Both the input and output go right to this chip, and there are parts in the way of the chip to try to read the chip numbers. (which likely would not match anything anyhow). [not to mention I cant see well enough to read chips anymore].   What is most weird, there is a LED on the board which says "LED" and the caps have numbers next to them (in english).   I plan to contact the seller to ask for an email containing the schematic or a photo showing what is what.....   This is the first time I have ever run across a PCB labeled in chinese...

Steve & Lynn <cheryl@must.die>: Feb 23 04:52PM > I am not a member of any organized political party. I am a Democrat.   O.K. NOW THAT EXPLAINS WHY YOU'RE SO GAY

Ralph Mowery <rmowery28146@earthlink.net>: Feb 23 04:41PM -0500 In article <MPG.33194c2971864c29c@news.plus.net>, gravity@mjcoon.plus.com says...   > Is there anything that I can do for some more diagnosis? The > motherboards is a GA-8ISXT-FS and the PSU FSP300-60ATV with a 20-pin > main power connector.   AT one time many mother boards were failing because the capacitors on them were defective. Look at some of the big ones tops, especially near th eprocessor and those coils of wire. If they are sort of dome shaped instead of flat, that would be the place to start.   Sometimes you could heat the board and it would start and then run for a long time. Cut it off and you had to heat it again to get it to start.   I sent a couple of boards back for replacement due to this problem years ago.

sam@repairfaq.org (Samuel M. Goldwasser): Feb 23 03:48PM -0500 > When this one craps out/gets too weak I'll do a post mortem, but I > suspect it uses resistance wire which changes resistance over time. > If the problem is that, then there's no fixing it.   Join the club. :( :) I've had 4 or 5 (yeah I'm a sucker for Sunbeam blankets) but don't want to be too critical of Sunbeam - they have replaced several under warranty and replaced one totally.   Thee typical symptoms are that they do tend to get weaker over time, but some die totally. The weakening may be related to the PTC (Positive Temperature Coefificnt) of resistance of the wire used as the heating element. It's self limiting so claimed to be safer since even scrunching up the blanket should not result in an excessive temperature rise. However, the change in resistance may not be totally reversible. I doubt using preheat makes a big difference. Since the power to the heater is pulse width modulated (around an 80 second cycle - yes, that long!), running at lower heat doesn't necessarily help either.   When they totally die, I assume it's a bad connection issue, possibly at the "module" - the wart attached to the connector, which has a couple of discrete components inside and nothing else.   And I do now record the current used when new. ;-)   Google "Sunbeam blanket problems" or something like. There's a lot out there.   -- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/ Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/ +Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm | Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html   Important: Anything sent to the email address in the message header above is ignored unless my full name AND either lasers or electronics is included in the subject line. Or, you can contact me via the Feedback Form in the FAQs.

micky <NONONOmisc07@bigfoot.com>: Feb 24 07:15PM -0500 In sci.electronics.repair, on Fri, 24 Feb 2017 16:46:20 -0500, Pat >>who is normally a stickler for things, agreed that I didnt' have to have >>a battery to run the alarm, since outages are so rare here.   >That seems like an odd thing for your friend to say. Alarm systems   Thanks for all the advice. It will be valuabe for many people.   He knows the kind of crimes that happen here, and he knows them by neighborhood too (a few years ago he had 800 or maybe it was 1200 customers) , and where I live they don't use fancy tricks like cutting the power or phone lines. Did I mention I don't live near the Vanderbilts, or even any doctors or lawyers. (there also aren't many burglaries because a lot of burglars know there is more money in other n'hoods** )   Where I live they break in. If an alarm goes off, they grab what they can quickly and they leave quickly.   We did discuss routing the phone line, whether the alarm needed to interrupt the phone line to the phones (because that would be difficult to arrange here. The phone line no longer goes to the basement. I just use a cordless phone in the basement, where the alarm is, so the alarm telephone line and the telephone telephone-line are wired in parallel.). He pointed out three reasons why it should.   If the alarm is between the phones and the phone company, were I on the phone when the alarm went off, the call would be interrupted, and that would indicate (though not 100%) that the alarm had gone off. But I would also hear the siren , whether I'm on the phone or not. He knows that but he was being complete. (Plus I don't set the alarm when I'm home. Maybe if I get old and feeble I will.)   If he wants to do remote maintenance to the alarm, it works better, but he pointed out, all I would have to do is turn off my phone answering machine and not answer the phone.   If the alarm does not disconnect the phones, when the burglar comes in he can take a phone off the hook and stop the alarm from dialing out. (Is that true. i thought since touch tone, one phone could dial out even if another phone was off the hook. (I think I tested this once.) I thought the burglar would have to dial a number or two before the alarm finished, or started, dialing. That's not so hard because the phone doesn't dial absolutely immediately. It gives the owner a 10 or 20 seconds to put in the code for example. Maybe he meant all that but he simplified it for me.)   >your house. Same with the phone lines used to dial out for help. It >is easy to cut land lines. That's why newer alarm panels often use >cellular.   He sells those too.   > Not perfect, but it takes more knowledge and equipment to >jam a cellular call than to cut landline phone wires.   ** Not many burglaries. 9 years ago I went away for 8 weeks, couldn't get the alarm working in time, but the house was unchanged when I got back. And I've seen houses sit vacant for months without any damage at all. OTOH, kids broke into one vacant house and used it as a clubhouse until the police scared them out. And 34 years ago, the first summer, someone kicked open my front door though he didn't steal anything***, and another time two lawnmowers were stolen (both were very broken), and another a crummy bicycle without a seat or post was stolen. but the last two incidents didn't require going into the house.   ***My burglar alarm was sitting on the bed or the floor, in pieces. I hadn't taken taken the parts out of the boxes yet. But I stayed home from work the next day and installed it.

Clifford Heath <no.spam@please.net>: Feb 25 10:20AM +1100 On 24/02/17 17:05, micky wrote:   > More things I should have known in advance**.   > So if one SIM is removed, will the other do 3G, regardless of which SIM > is left in?   I think so, but it probably depends on the phone.   The advertising for the phone will often say "2nd SIM, standby only", which is the give-away that it's only 2G or worse.   > Or does it have to be in slot #1?   Again, it probably depends on the phone. Only one can log in to the 3/4G network. I think that a true dual SIM phone needs to duplicate parts of the networking hardware so it acts like two phones; but I am not an expert in such things.   > (I just got the second SIM in the mail today, but I can't use it until > mhy trip starts in 2 weeks.)   I wanted a dual SIM phone so I can get SMS (and possible family emergency calls) while using local data. In any place where 2G has been shut down, that doesn't work, so I might as well just have a single SIM phone, and switch over each evening to get delayed SMS.   > **Actually today is far better to learn this than after my trip. It's > not in advance of buying the phone but it's in advance of using this > part.   Well, I've just bought a new dual-SIM phone, but not because it was dual-SIM.

oldschool@tubes.com: Feb 25 03:52AM -0600 >at least several thousand Watts. I borrowed a set of ear muffs and sat back >for a show!   >Jon   I was at several Grateful Dead concerts in the late 60's and afterwards. I never saw any such thing. Are you sure you were not "tripping"? That may have just been a common 6L6 tube in a guitar amp, and your hallucinations made it look really BIG.... :)   Who ever heard of wearing earmuffs at a Grateful Dead concert.....   And since you mentioned it. What the hell is wrong with them British? Valves are plumbing parts. Tubes are electronic parts!!!   Seriously, I have heard of using AM transmitter tubes for audio amps. I dont know what those tubes are numbered, or how much power they output, but I know that many AM radio stations have power output in the thousands of watts range. But to use that kind of tube would require custom output transformers that would likely mimic the pole transformers used to feed our homes....   And just for historic value, the original 1969 Woodstock concert ran Somewhere between 3500 watts to 12,000 watts, using Mcintosh mi350 monoblock tube amps for their PA system. The article below seems to conflict whether it was 3,500W or 12,000W. Either way, that PA system had to cover a very large area, and apparently it did the job.   http://www.mylespaul.com/forums/showthread.php?t=100811   These Mcintosh MC3500 power amps have EIGHT power output tubes 6LQ6/6JE6B. These amps had an output of 350W. (mono).

Jon Elson <jmelson@wustl.edu>: Feb 24 04:11PM -0600 > channel...... (And an output transformer about 3 foot big, weighing > close to the weight of a Harley motor cycle, and costing 10X the price > for a brand new Harley)..... No, certainly not! You use the modulator from an old AM broadcast transmitter. I was at a Grateful Dead concert in 1969 and they wheeled out this THING on the stage with big glass globes, and when they lit up I realized they were TUBES (valves to the British)! Not sure of the type, but at least several thousand Watts. I borrowed a set of ear muffs and sat back for a show!   Jon

Ralph Mowery <rmowery28146@earthlink.net>: Feb 20 05:54PM -0500 In article <21omac9vnp8nbi8g7gd8utr45blru7ej4n@4ax.com>, etpm@whidbey.com says... > get a Tek 465B. I found one for about a $100.00. It still works great > and has always been trouble free. > Eric     I looked on ebay and did not see anyting in that price range that I would buy. There were some , but sold as is and not guranteed to work. They probably will, but I would not take a chance on one if I did not think I could repair it. Most did not have any probes either. Some comming out of China are ok and you can get a pair for around $ 20.   I agree with the 465B scope, Probably the best analog scope for the money. I bought one off ebay a few years ago, but it was over $ 200 without the probes. For that kind of money I would go to about $ 300 and get one of the China digital scopes.

sam@repairfaq.org (Samuel M. Goldwasser): Feb 18 03:38PM -0500 > me at "FAKE NEWS" on You Tube (I do not open e-mails for fear of being > hacked ) Thank you , Don Young ( looking forward to a reply and some > help )   I hope this isn't too controversial. :)   I would recommend you get a guaranteed working Tek analog scope on eBay, probably $100, $150 at most. The newer the better, but if it is working when you get it, it will probably serve you long enough to satisfy your needs.   DSOs are great once you have some familiarity with what to expect, but can be very deceiving if you don't.   -- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/ Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/ +Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm | Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html   Important: Anything sent to the email address in the message header above is ignored unless my full name AND either lasers or electronics is included in the subject line. Or, you can contact me via the Feedback Form in the FAQs.

Jeff Liebermann <jeffl@cruzio.com>: Feb 23 08:44AM -0800 On Wed, 22 Feb 2017 20:47:57 -0500, micky <NONONOmisc07@bigfoot.com> wrote:   >I have one of thoe little 2.5" LED flashlights, that have 9 small LEDs >and use 3 AAA batteries. It's like the ones that Harbor Freight >sometimes gives away free, same size, but nicer.   Did you notice that almost all such flashlights are made from aluminum, not plastic, which would be cheaper? That's because aluminum makes a good heat sink to get the heat away from the LED's. LED's loose output and efficiency when hot, so it pays to keep them cool. The COB style of LED mounting is quite common in larger flashlights, which offer a heat conductive path from the LED to the aluminum heatsink case.   >warm.   >It's still really bright, but if it's noticeably warm, how long can the >baterries really last? Certainly not two days. ?   No, it won't run forever. AAA alkaline batteries are good for 1000ma-hr each. At something less than 4.5V for 3 batteries, that's 4.5 watt-hrs. Commodity LED's generate about 50 lumens/watt, so if your Harbor Freight flashlight managed to belch 15 lumens, it will consume 0.3 watts. Runtime is therefore an optimistic: 4.5 watt-hrs / 0.3 watts = 15 hrs. It's probably less because I didn't bother throwing in losses in the current source, decrease in battery voltage as it runs down, and heating effects. But, it should give you a ballpark guess as to how long it will run. My guess(tm) is it will run about 8 hrs with a new set of batteries.   >I once, recently, forgot the screen was lit on my 5.5" smart phone and >only noticed because it felt warm in my pocket.   If your smartphone as a battery usage graph, like all Android phones, you'll find that it also has a list of which applications are sucking the most power. The backlighting for the OLED screen is invariably the highest. If you don't talk on your phone, and don't run any apps, the battery life of your phone will be totally dependent on the brightness setting and efficiency of the OLED display, which is about the same 50 lumens/watt as your white LED. (Yes, I know there are press releases for >100 lumens/watt, but those are under laboratory conditions).   >It's got a proximity sensor but I don't remember what it's supposed to >do.   Never heard of it. Maker and model number?   -- 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

Michael Black <et472@ncf.ca>: Feb 24 06:47PM -0500

Steve & Lynn <cheryl@must.die>: Feb 24 11:40AM > On Monday, February 13, 2017 at 3:05:42 PM UTC-5, jurb...@gmail.com wrote:   > Peter Wieck > Melrose Park, PA   Laughable Ill-Informed Blaming Entitled Race-Bating Anti-Capitalist Loudmouth

frank <frank@invalid.net>: Feb 25 06:29PM Hi all, I'm trying to keep an old TV alive, it's an old 14CT2306/20S from Philips and it's the only think that fits into a furniture space in my parent's house, so that will not be replaced. I'm keeping it alive for 30+ years now. The LOPT developed some leaks in the past years but they where on the external side so I was always able to scratch the hole zones and put some epoxy that cured the leak. Lately it developed a nasty leak to the internal core, so it's time to find a replacement for it. I ordered an HR-6098 LOPT on ebay based on diemen HR equivalence and when it arrived, I noticed that it lacks pin 1. On the diemen site, the HR-6098 indeed has pin 1, schematics and actual chassis both agree that pin 1 is needed as horizontal signal going into an LM339 comparator, so I think I can't put this transformer in place of the original one. The ebay seller just said that since it's stamped with the correct name, it must be it and I'm just not able to install it correctly :) Is there any chance that the seller is right or my only option is asking for a refund via PayPal? What could be going on here? I wouldn't believe it's viable to make fake LOPT anyway. Maybe a mis-labeled unit that was so similar to the rigth one?   Thanks Frank

micky <NONONOmisc07@bigfoot.com>: Feb 22 08:41PM -0500 Years ago, I was told not to play my stereo with no speakers, for fear of somethun' or other. Of course that was 1968, a good year for audio.   Is this still an issue with current electronics, like audio amplifiers and burglar alarm amplifiers?   Now I have a home burglar alarm that might be in the alarm status. I can't tell because I disconnected part of it, until I can find out how to disarm it.   I have two horns and a siren driving amplifier board, so that they're louder than the mere alarm control panel can provide. I have a glass fuse in the line to each speaker.   So if I take the fuse out but the siren driver is still functioning, do I risk burning it out? Even if it's like this for say, 20 hours?   Or can it go like this with no harm to itself?   What if I disconnect the siren driver from the control panel? They're separate boards. Do I risk burning out the output of the alarm control panel, if say it is run. again, 20 hours?   Or can it go like this with no harm to itself?     Those are the questions. The rest here is just a narrative, soon to be a major motion picture.   20 hours is how long I need to look into it, sleep, and then contact my friend who runs an alarm business. But I'd really like to do as much as possible on my own. He's constantly doing favors for me and a couple days ago he wanted to send over his technician to finish the installation for me. I can offer to pay; i can insist on paying, but I know he won't let me, and, trust my judgment, he probably wants the kavod of helping me more than he wants the money. Plus my own ego is involved in wanting to do it myself...., so I really shouldn't be asking you any questions either. But it's different. None of you are coming to my house to do it.   The reason it's running is that I tried the original default master code, several times, and it didn't work. It wouldn't arm the system, but I wanted to hear if the siren worked (this system has never been tested before) and soon I got the bright idea to arm it another way. there is an Away button which when pushed for 2 seconds arms it without the code. Well the siren works, as well as it did when I had my previous system installed (designed and installed by me, but it burned out after 15 years. Lightning?) but I didn't look far enough ahead to realize still didn't have a code that worked and I have no way to turn it off.   Well, I unplugged it, and the battery hasn't been charged in 9 years, so that turned it off, but I need to work on it and the moment I plugged it in again, it armed itself.

Steve & Lynn <cheryl@must.die>: Feb 22 06:27PM > This is slightly off topic....     > From what I am seeing, those transformers are all under rated. A friends > house has 200A service and his transformer is only 8KVA.   WHAT SIZE TRANSFORMER DO YOU SUPPOSE SITRE MAGANA NEEDS IN ORDER TO PLAY WITH HIS OWN SHIT?   HOW MANY VOLT-AMPERES DOES ONE NEED TO FUCK A 72 YEAR OLD MAN AT A GAY ORGY?   HOW MANY AMP SERVICE DO YOU NEED TO CUT A HAMSTER TO PIECES WITH A PAIR OF SCISSORS?

ohger1s@gmail.com: Feb 27 04:51PM -0800 > * If anyone knows of a COMPLETE listing that can be downloaded, such as > a PDF file, please post the URL. (or even a text file). I am not finding > anything that's complete......   The IB3 is easy. The IB3, 3A3, 2AV2 etc. are all HV rectifiers, and the filaments were designed to run off parasitic windings of the HV transformers. The less turns the better I guess. The 1B3 was for B&W TVs, the 3A3 for color TVs which, not coincidentally, had about twice the HV as the B&W versions, so a turn or so around the core would give the correct voltage.   Tubes like the 800 series or the early 4 pin radio tubes were never part of the standard numbering scheme, and as for the others, if you consider the many thousands of tubes from dozens of manufacturers that were pigeon-holed into the handful of basic types, you'd need unique letters just to identify them.

Phil Allison <pallison49@gmail.com>: Feb 27 07:26PM -0800 > And then there were those old 1B3 tubes in TV sets. Where did the 1 volt > heater voltage come from? (and why didn't they just stick with 6.3 volts > like other tubes?)   ** Like all rectifier tubes, the cathode is the output point and in this case can be up to +26kv above ground.   The 6.3V heater chain used by other tubes cannot be used as a 26kV insulation barrier would stop all heat getting to the cathode. So the tube cathode is directly heated by a winding that floats at the HT voltage.   http://www.radiomuseum.org/tubes/tube_1b3.html   Since the load current is 50mA max, a low powered heater is enough - 1.25V and 200ma do the job.   The 1.25V needed is conveniently derived by a single turn around the HOT core, carried out with wire insulted to stand 20kV or more.     .... Phil

Chuck <chuck@mydeja.net>: Feb 27 10:59AM -0600 On Sun, 26 Feb 2017 14:06:31 -0800, John Robertson <spam@flippers.com> wrote:     >Suggestions appreciated!   >Thanks,   >John :-#)#   If the problem isn't HV arcing, check or replace parts from pin3 of the flyback including the 2 AFC diodes D401 and 402. The diodes on this line I'd just replace.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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