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Phil Allison <pallison49@gmail.com>: Feb 22 04:34PM -0800 Bob Engelhardt wrote:     > I can't imagine myself attaching a lead to a high voltage source before > it is attached to a meter. Or switching the meter connection after it's > attached.     ** But you can imagine the plug coming out of the meter unintentionally, then being replaced while "hot" or touching ground/chassis and causing a massive short.     > Maybe it's something one starts doing when the plugs are fully enclosed.   ** Shrouded plugs make it safe to leave probes attached to a high voltage or high current source.   Been a standard feature of any decent DMM for decades now.     .... Phil

"jfeng@my-deja.com" <jfeng@my-deja.com>: Feb 22 06:13PM -0800 On Monday, February 22, 2016 at 4:34:57 PM UTC-8, Phil Allison wrote: > being replaced while "hot" or touching ground/chassis and causing a massive > short.   > .... Phil Based on a sample of one, that is extremely unlikely. The shroud on the plug fits very tightly in the case, and there is additional friction from the banana plug. Even if you snagged the meter, you will probably pull the probes out ot the CUT before the plugs come out of the meter.   BTW, the one significant flaw in my HF meter is that it does not have a low-battery indicator. The calibration seems very good with fresh batteries, but gets very bad when the batteries are weak.

Jeff Liebermann <jeffl@cruzio.com>: Feb 22 08:50AM -0800 >The way I read that is that's a *replacement* for a Power-Sonic battery, >and not actually a Power-Sonic battery. The price also makes me think >it's a junk battery, and not actually a Power-Sonic.   That's also the way I read it. However, note the battery weights. From the respective web piles, the real PowerSonic weighs 4.80 lbs, while the Battery Sharks clone weighs 5.25 lbs. I differentiate battery quality of identical size batteries by their weight, which is an indication of how much lead is in the battery. Based on that metric, the weight differnce (10%) suggests that the Battery Sharks clone is the better battery.   Of course, Battery Shark could be inflating the battery weight because they know about the weight trick. Double checking: <http://sigmastek.com/files/specsheets/SP12-7(T1).pdf> Yep, Battery Sharks is lying on their web pile. The data sheet shows 4.52 lbs, which is LESS than the real Power Sonic. The battery is probably crap and I don't think I would trust the dealer.   Incidentally, you can also get the same Sigmastek battery from the Battery Sharks people for $9.69 without the claim of PowerSonic equivalence. <http://www.batterysharks.com/SigmasTek-SP12-7-p/sp12-7_b12-7.htm>   -- 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

Jeff Liebermann <jeffl@cruzio.com>: Feb 22 08:57AM -0800 On Mon, 22 Feb 2016 08:50:20 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >Of course, Battery Shark could be inflating the battery weight because >they know about the weight trick. Double checking: ><http://sigmastek.com/files/specsheets/SP12-7(T1).pdf>   Also: <http://sigmastek.com/EN/products.cfm?page=products&seriesID=1&productID=108> I just found a reason to buy Sigmatek batteries. The upper right of the page proclaims that they offer "Passionate Customer Service". It might be worth buying their battery just to try out their customer service.   -- 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

Sofa Slug <sofaslug@invalid.invalid>: Feb 22 05:36PM -0800 On 2/16/2016 2:40 PM, Bill Baxter wrote: > I have a Cyberpower 550VA USP whose battery needs replaced. I see many > options during googling, but I'd like to find something that will last. > I know some of the generics aren't the greatest. Suggestions? Thanks!   If the original battery served you well, the first thing I would do is take it out and have a careful look at it. If you don't mind a little online research, chances are very good that you will be able to find a literal twin of the OEM version with an aftermarket brand on it.   Oh... and +1 on the Power-Sonic batteries - I have had good luck with those as well.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Feb 23 08:43AM +1100 On 22/02/2016 4:06 PM, Jeff Liebermann wrote: > supplying enough information to even diagnose the alleged fuser > problem. If you can't describe what's wrong with the fuser, could you > at least describe what inspired you to purchase a new printer?   **Every reference points towards me buying a new fuser. The cheapest option will be more than AUS$300.00. And that may not fix the fault. I'd prefer not to spend a huge chunk of cash on an ancient, but quite decent, printer. That said, I have just located a service manual for the 3000, 3600 & 3800 (but not the 'N' variant). It is a very large file and will take some time to complete, but, hopefully, will shed some light on what is inside the fuser and how to pull the damned thing apart.   > that spins the scanning mirror. Pre-warming the fuser on startup > would take over a minute for a cold start. The LJIIIp was a slightly > faster version of the worlds slowest small laser printer.   **Nonetheless, the little HP Laserjets never gave me a moment's trouble. Slow, but reliable (for me).   > In my never humble opinion, the 3600N is better than any of the > alternatives you've listed, and will probably last forever if you take > care of it.   **OK. I will take that approach. I should be able to survive on what I have lying around for the present. I just found a Brother laser printer, which should do most of my printing needs for the next few weeks (it'll take that long to import a new fuser).     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Feb 23 09:13AM +1100 On 22/02/2016 4:06 PM, Jeff Liebermann wrote: > supplying enough information to even diagnose the alleged fuser > problem. If you can't describe what's wrong with the fuser, could you > at least describe what inspired you to purchase a new printer?   **Good news bad news time. I now have the service manual for this device. No useful schematics. Just block diagrams and hundreds of pages of mechanical drawings and photos. Quite comprehensive in it's own way. The good news is that I now have a proper interpretation of the fault code.   50.8 = Low fuser temperature (Subthermistor)   Would I be crazy to buy one of these?   http://www.ebay.com/itm/RM1-2764-RM1-4349-HP-Color-LaserJet-3000-3600-3800-CP3505-Fuser-Unit-220v-/271729961017?hash=item3f445e2839:g:zpcAAOSwnDxUgFp3     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Adrian Caspersz <email@here.invalid>: Feb 22 10:33PM On 21/02/16 06:22, Trevor Wilson wrote:   > Any suggestions will be welcome. After spending almost 300 Bucks on > toner, I am keen to keep this sucker going for another few years. I'd > prefer not to spend 500 Bucks on a new fuser though.   You are patient. These things are sloooooowww.   Whatever, keep a lookout on the secondhand market for these.   I find the current HP driver that allegedly works on Windows 7 rather buggy, and as part of a company job I did building a 2012R2 print server, we decided the best course of upgrade action was to unfortunately throw out the printers. I bet others came to that conclusion.   -- Adrian C

"Mr. Man-wai Chang" <toylet.toylet@gmail.com>: Feb 23 06:42AM +0800 On 2/21/2016 2:22 PM, Trevor Wilson wrote: > and bought a bunch of toner cartridges for the thing. As luck would have > it, it has just thrown up a fuser error (50.8). At first, the error was > intermittant, now it is permanent. Questions:   Did you phone/email HP Australia if not US?   Maybe that's why the printer was discarded in the first place....   -- @~@ Remain silent. Nothing from soldiers and magicians is real! / v \ Simplicity is Beauty! May the Force and farces be with you! /( _ )\ (Fedora release 23) Linux 4.3.5-300.fc23.x86_64 ^ ^ 06:27:01 up 6 days 13:21 0 users load average: 1.00 1.02 1.05 不借貸! 不詐騙! 不援交! 不打交! 不打劫! 不自殺! 請考慮綜援 (CSSA): http://www.swd.gov.hk/tc/index/site_pubsvc/page_socsecu/sub_addressesa

Clifford Heath <no.spam@please.net>: Feb 23 09:36AM +1100 On 23/02/16 09:13, Trevor Wilson wrote: > The good news is that I now have a proper interpretation of the fault code. > 50.8 = Low fuser temperature (Subthermistor)   Can you measure the actual temperature of the fuser and compare it with what the manual says?   It'd be a shame to buy a whole new fuser if it's only the thermister that's bad.   Clifford Heath.

Jeff Liebermann <jeffl@cruzio.com>: Feb 22 04:03PM -0800 On Tue, 23 Feb 2016 08:43:37 +1100, Trevor Wilson >3000, 3600 & 3800 (but not the 'N' variant). It is a very large file and >will take some time to complete, but, hopefully, will shed some light on >what is inside the fuser and how to pull the damned thing apart.   Somehow, I seem to have missed the part where you describe what inspired you to purchase a new printer and what failure mode you're experiencing with the fuser. Perhaps it can be repaired. I think you'll find the rebuild kit I previously mentioned a better and cheaper alternative at $80: <http://www.ebay.com/sch/i.html?_nkw=hp+color+laserjet+fuser+rebuild>   -- 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

Jeff Liebermann <jeffl@cruzio.com>: Feb 22 04:19PM -0800 On Tue, 23 Feb 2016 09:13:00 +1100, Trevor Wilson >of mechanical drawings and photos. Quite comprehensive in it's own way. >The good news is that I now have a proper interpretation of the fault code.   >50.8 = Low fuser temperature (Subthermistor)   Thank you for delivering the error message. <http://www.all-laser.com/a50service/> I've seen that error message on other model HP printers. In my experience, it can be anything from a loose connection on the ends of the ceramic slab heater element, to cracks in the heater element. Also, caked on toner onto the thermistor temp sensor will cause a low temp reading. Measure the resistance of the heater element from end to end and you should see about 15 for 117V and twice that for 220V. I think I know where I can find a 3800 to measure, or just ask in the HP forums or FixYourOwnPrinter forums.   This article suggests that it might be low line voltage: <http://www.fortwayneprinterrepair.com/wordpress/2011/11/06/hp-color-laserjet-3000-3600-3800-and-cp3505-50-1-fuser-error/>   Also see: <http://www.fixyourownprinter.com/posts/42184> I'll try to find the unspecified service note, but so far, I'm not having any luck finding it.   Meanwhile, dig through this mess on 50.1 errors and see what you can excavate: <https://www.google.com/search?q=hp+color+laserjet+50.1+fuser+error>   >Would I be crazy to buy one of these? >http://www.ebay.com/itm/RM1-2764-RM1-4349-HP-Color-LaserJet-3000-3600-3800-CP3505-Fuser-Unit-220v-/271729961017?hash=item3f445e2839:g:zpcAAOSwnDxUgFp3   Good find. I missed that one. Yes, that should work for 220V. I checked the numbers. Since the rebuild kit does NOT include a heater element, the replacment from China may be your only reasonable option.   -- 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

Jeff Liebermann <jeffl@cruzio.com>: Feb 22 04:39PM -0800 On Mon, 22 Feb 2016 16:19:46 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >Meanwhile, dig through this mess on 50.1 errors and see what you can >excavate: ><https://www.google.com/search?q=hp+color+laserjet+50.1+fuser+error>   Sorry. 50.8, not 50.1. That's what happens when I get interrupted: <https://www.google.com/search?q=hp+color+laserjet+50.8+fuser+error>   Replacing the fuser does not guarantee a fix: <http://www.fixyourownprinter.com/posts/1001356>   Take a look at these typical HP fuser thermistors: https://www.google.com/search?tbm=isch&q=HP+fuser+thermistor> That a tiny thermistor is wrapped in Kapton or something heat resistant. What happens is that melted toner gets stuck to the face of the thermistor causing the toner to act as an insulator. The thermistor reads a lower temperature than what the fuser roller is actually running, causing the fuser to become excessively hot. Eventually, the fuser gets too hot and cracks the heater element, producing an error message. If you're lucky, and catch it before the heater cracks, just cleaning the ossified toner off the face of the thermistor is usually sufficient to fix the problem.   This web site offers anything between 20 and 1000 ohms as acceptable heater resistance for 220V: <http://mindmachine.co.uk/products/HP_Error_50X.html#diagnosing-fuser-faults> I still can't find a good target value for the 3600.   -- 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

Jeff Liebermann <jeffl@cruzio.com>: Feb 22 04:48PM -0800 On Mon, 22 Feb 2016 16:39:10 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   One more and I'll go away and do something useful.   I think the HP Color LaserJet 3600N has three thermistors on the fuser roller. The main one is in the middle. The other two, at each end of the fuser roller, are called sub-thermistors. One of them is covered with toner crud, or has otherwise failed. Be sure to check the fuser film for mechanical damage.   -- 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

DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org>: Feb 22 05:57PM On Mon, 22 Feb 2016 11:42:12 -0500, Ralph Mowery wrote:   > size of the cable. The reason rg-6 size is used is for lower losses at > higher frequencies. It is less expensive and able to be bent and > handled in a house easier than the rg-11 size.   Nobody ever used RG-11 in a house. It was always RG-59 and now with the channel count and digital internet being added, most in-house installs are RG-6 throughout, unless it is a cheap ass cable company.   It is not mere wire resistance either. The capacitance is also a factor in why RG-6 is better than RG-59.   > The main loss in the cable up; to about 1000 MHz is the resistance loss > of > the conductors.   Another reason why mere foil shielding does not ring true. This is why the center conductor is not a copper plated steel core, but a copper CLAD steel core.   > loss. The foil is used to provide a very good shield to keep the RF > inside the cable, and the braid is mainly to provide a way to crimp it > for a good electrical connection.   There are different braid fill levels available. It comes down to what the cable company wants to spend on their build.

"Ralph Mowery" <rmowery28146@earthlink.net>: Feb 22 01:57PM -0500 "DecadentLinuxUserNumeroUno" <DLU1@DecadentLinuxUser.org> wrote in message news:nafi66$1au8$1@gioia.aioe.org...   > It is not mere wire resistance either. The capacitance is also a factor > in why RG-6 is better than RG-59.   The capacitance has almost nothing if anything at all to do with the losses at the cable frequencies.   If you look at the charts the capacitance is nearly the same and often the rg-59 is less than the rg-6.. The main losses is the I squared R loss of the conductors.

rickman <gnuarm@gmail.com>: Feb 22 02:12PM -0500 On 2/21/2016 6:06 PM, John G wrote:   > I'll believe Aluminium or steel I must admit to only a little actual > experience. > Some Cable guy should give an actual answer.   The stuff I use has both copper center conductor and braid. Most RG-6 uses a steel center conductor with a copper plating since the skin effect limits current flow to the surface at high frequencies and the steel provides more strength for pulling and aerial runs.   --   Rick

rickman <gnuarm@gmail.com>: Feb 22 02:20PM -0500 On 2/22/2016 1:57 PM, Ralph Mowery wrote:   > If you look at the charts the capacitance is nearly the same and often the > rg-59 is less than the rg-6.. The main losses is the I squared R loss of > the conductors.   Looking at the chart of loss vs. frequency for Belden 1694A Coax I see 0.24 dB at 1 MHz, > 3 dB at 270 MHz and > 6 dB at 1000 MHz. I don't see any factor for frequency in I^2R. I suppose this could be skin effect increasing the conductor resistance.   How do you tell when the losses are mostly due to the dielectric?   --   Rick

"Ralph Mowery" <rmowery28146@earthlink.net>: Feb 22 02:47PM -0500 "rickman" <gnuarm@gmail.com> wrote in message news:nafms0$6dr$1@dont-email.me... > any factor for frequency in I^2R. I suppose this could be skin effect > increasing the conductor resistance.   > How do you tell when the losses are mostly due to the dielectric?   It is the skin effect of the center conductor mostly up to around 1000 mhz. Below that the dielectric has very little loss.   There are places that show how to calculat the various losses depending on the material and frequencies, but the math gets involved.   There is a chart here that shows the relative effect. https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjowZuWkIzLAhVFNT4KHRUQBukQjRwIBw&url=http%3A%2F%2Fwww.rfcafe.com%2Freferences%2Farticles%2FJoe-Cahak%2Frf-connectors-cables-joe-cahak-6-2014.htm&psig=AFQjCNGIEOiXBCpLe3a7WLhDueMCfF231w&ust=1456256383257029

"Ralph Mowery" <rmowery28146@earthlink.net>: Feb 22 02:56PM -0500 "rickman" <gnuarm@gmail.com> wrote in message news:nafms0$6dr$1@dont-email.me... > any factor for frequency in I^2R. I suppose this could be skin effect > increasing the conductor resistance.   > How do you tell when the losses are mostly due to the dielectric?   If you really want to get into it, here is a place that gives the info. Lots of math to look through. Much easier just to look at the chart for a good indication of where the losses are.   http://www.rfcafe.com/references/articles/Joe-Cahak/rf-connectors-cables-joe-cahak-6-2014.htm

DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org>: Feb 22 10:14PM On Mon, 22 Feb 2016 14:12:31 -0500, rickman wrote:   > uses a steel center conductor with a copper plating since the skin > effect limits current flow to the surface at high frequencies and the > steel provides more strength for pulling and aerial runs.   Nope. Copper plating is too thin. It is referred to as "copper clad".   Same thing for ground rods, except the reason in that case is abrasion durability.   Goddamned cross-posting retards.

M Philbrook <jamie_ka1lpa@charter.net>: Feb 22 06:41PM -0500 In article <Bf6dnb0NpNQX-lbLnZ2dnUU7-R2dnZ2d@earthlink.com>, rmowery28146@earthlink.net says... > Lots of math to look through. Much easier just to look at the chart for a > good indication of where the losses are.   > http://www.rfcafe.com/references/articles/Joe-Cahak/rf-connectors-cables-joe-cahak-6-2014.htm   Or I could go into the archives at work "Brand-Rex", and get the original designs specs and charts. Yes, those were the days.   We just retired the very first irradiation cross linking line ever made for production use of any product. The actual first cross linker irradiation unit for non commerical use was for the airforce, in a hanger.   Our unit now sits on the floor waiting for a home in some antique shop, 170k Watt version. It was getting hard to find chips to keep it operating. Many BB chips, round can op-amps. The osc for the magnetic amp was a UNI transistor that drove a transistor Flip Flip to generate a 100Hz sweep for the amp. In that circuit was wave shaping components to get a step peak on the out sides of the sweep before it changed direction.   Neat stuff for back then, real engineers not uC coders!   Jamie

Whiskers <catwheezel@operamail.com>: Feb 22 10:07PM >> Now we finally have a way to list *all* the devices on the network!   > Of course it is also a closed source program, as far as I can see, so > for all we know, it reports all those devices back "home"   So start 'etherape' or some other packet sniffer before running fing.   -- -- ^^^^^^^^^^ -- Whiskers -- ~~~~~~~~~~

dansabrservices@yahoo.com: Feb 22 09:23AM -0800 > Hello..I cannot eject the tape. It will not play, rewind either. It is a VERY special home video tape that I don't want to damage. I cannot find any local repair shop to look at it and even SONY says they can't find anyone to repair. Can you help!! > Thank you..   Where are you located?   Dan

John-Del <ohger1s@aol.com>: Feb 22 09:46AM -0800 > Hello..I cannot eject the tape. It will not play, rewind either. It is a VERY special home video tape that I don't want to damage. I cannot find any local repair shop to look at it and even SONY says they can't find anyone to repair. Can you help!! > Thank you..   If the tape is important, don't force the basket up or you'll destroy it. Most likely the tape is still loaded around the head. The transport won't allow eject until the position encoder tells the computer that the tape is safely back in the cassette.   If you just want the tape out most TV shops would be able to safely extract the tape. If you want the machine repaired, then your options are limited. It's been years since we've taken any in for repair. If you can get the tape out, see if you can borrow a machine or find one at a yard sale, then transfer the contents to digital.

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