- Microwave oven - 7 Updates
- Inverter Generator - 10 Updates
- Centos Dell PowerEdge 830 PCIe Training Error & SATA port 0 not found - 8 Updates
| Cursitor Doom <curd@notformail.com>: Mar 22 07:37PM Hi all, I have had the same Daewoo microwave oven since I bought it new 7 years ago and it's always performed *perfectly* up until today. This morning I stuck some bread in it to defrost and it came out still frozen. No trace of any heat at all. The platter rotates, the light comes on, the timer counts down, the fan runs; all is working fine except for the total absence of heat. I'm given to understand that microwave ovens typically have a working life of only around 2 years nowadays, so I'd really like to fix this one up rather than replace it with something inevitably inferior. Any suggestions as to what to check for? I have the gear to measure up to 50kV if necessary, and I'd guess the magnetron HT is considerably less than that figure. So... where to start looking first? -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| tabbypurr@gmail.com: Mar 22 02:18PM -0700 On Friday, 22 March 2019 19:37:05 UTC, Cursitor Doom wrote: > suggestions as to what to check for? I have the gear to measure up to > 50kV if necessary, and I'd guess the magnetron HT is considerably less > than that figure. So... where to start looking first? Likely candidates are the HV diode & HV fuse. Of course it can be other things. And of course they're in the killer section. NT |
| John-Del <ohger1s@gmail.com>: Mar 22 02:46PM -0700 On Friday, March 22, 2019 at 3:37:05 PM UTC-4, Cursitor Doom wrote: > suggestions as to what to check for? I have the gear to measure up to > 50kV if necessary, and I'd guess the magnetron HT is considerably less > than that figure. So... where to start looking first? The easy place to start is with the door switches. Microwaves usually have several as a fail safe. With the microwave running, watch the interior light carefully and listen for any change in sound as you slowly rock the door. If the light dims and you hear a buzz begin, you've got a cranky safety interlock switch. There could be a broken activator tang as well and it might be visible right on the door. Inside, the relays are known to develop cracks in the solder at the pc board, so leaning on the relay and edge connectors could restart the cooking. |
| Cursitor Doom <curd@notformail.com>: Mar 22 09:46PM On Fri, 22 Mar 2019 14:18:03 -0700, tabbypurr wrote: > Likely candidates are the HV diode & HV fuse. Of course it can be other > things. And of course they're in the killer section. Familiar territory then. I've spent god knows how many years prodding around inside the HT cages of CROs and whatnot. -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| tabbypurr@gmail.com: Mar 22 03:46PM -0700 On Friday, 22 March 2019 21:46:47 UTC, Cursitor Doom wrote: > > things. And of course they're in the killer section. > Familiar territory then. I've spent god knows how many years prodding > around inside the HT cages of CROs and whatnot. That's good. Re interlocks, they're designed to short out via a power resistor if any one fails to operate correctly. So usually interlock failure results in an oc shorting resistor - which is a hazardous state in which to run a nuke. So it's always worth checking continuity of the big resistor when you have the cover off. IME interlocks are low on the list of likely suspects. NT |
| Peter Jason <pj@jostle.com>: Mar 23 10:09AM +1100 On Fri, 22 Mar 2019 19:37:03 -0000 (UTC), Cursitor >suggestions as to what to check for? I have the gear to measure up to >50kV if necessary, and I'd guess the magnetron HT is considerably less >than that figure. So... where to start looking first? Replacing the lamp has me defeated. I buy a new mwave then. |
| Cursitor Doom <curd@notformail.com>: Mar 23 01:02AM On Sat, 23 Mar 2019 10:09:02 +1100, Peter Jason wrote: > Replacing the lamp has me defeated. I buy a new mwave then. I don't want a new one, though! The existing one is built to an amazingly high standard and the manufacturer has taken time and trouble to finish it beautifully as well. I'll struggle to find anything around today that comes close to that quality. -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| Ralph Mowery <rmowery28146@earthlink.net>: Mar 22 01:25PM -0400 In article <efc72184-b65b-478f-85aa-c87e0b1b42a0@googlegroups.com>, tabbypurr@gmail.com says... > > about 2 ot 3 dollars. They are powerful enough to run the inverter part > > of the inverter. > No sensible manufacturer is going to use a crystal` where they can use a ceramic resonator or a silicon oscillator built into the chip. And no sensible mfr is going to pay for a crystal plus a divide by massive number circuit when they can use a low frequency oscillator. If you can't see why there's nothing further for us to discuss. I guess that I used crystal too loose. Anyway the small processors and clock circuits for them are very inexpensive. Digikey has for sale crystal oscillators that can be programmed for most any frequency for around 2 to 3 dollars. I have even ordered them already programmed for about $ 4 each. I am sure in quanties of thousnads from the manufactor they are very inexpensive. |
| Fox's Mercantile <jdangus@att.net>: Mar 22 12:35PM -0500 On 3/22/19 12:25 PM, Ralph Mowery wrote: > any frequency for around 2 to 3 dollars. I have even ordered them > already programmed for about $ 4 each. I am sure in quanties of > thousnads from the manufactor they are very inexpensive. I have ordered those for a project. Certainly cheaper than having crystals made for $18-20 each. -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com |
| Ralph Mowery <rmowery28146@earthlink.net>: Mar 22 05:02PM -0400 In article <DaydndxaSbmMgAjBnZ2dnUU7-VOdnZ2d@giganews.com>, jdangus@att.net says... > I have ordered those for a project. > Certainly cheaper than having crystals made for $18-20 each. $ 10 to 20 is inexpensive for a special made crystal now. I only know of 2 places right now, Bomar that last report was $ 50 per crystal and minimum of $ 100 for an order. Another in England that is I think about $ 30 per crystal. |
| bitrex <user@example.net>: Mar 22 05:45PM -0400 On 3/20/19 6:57 AM, J.B. Wood wrote: > function in a variety of temperature/humidity environments I would think > frequency stability is important. Thanks for your time and comment. > Sincerely, Why is frequency stability important in a consumer-grade generator? It's important for generators that connect to the grid because they have to sync up to the grid. Most consumer grade generators are not designed to connect to the grid so what's wrong with 60 hz plus or minus a hz or two. An RC oscillator can do that. Nowadays most microprocessors have at least one general-purpose integrated RC clock oscillator. Appliances that use the 60Hz wall voltage for a timebase for anything don't really exist anymore not even cheap digital alarm clocks. |
| bitrex <user@example.net>: Mar 22 05:50PM -0400 On 3/22/19 1:25 PM, Ralph Mowery wrote: > any frequency for around 2 to 3 dollars. I have even ordered them > already programmed for about $ 4 each. I am sure in quanties of > thousnads from the manufactor they are very inexpensive. If the processor itself is timed from a crystal many uPs give the option of scaling down the system clock via a hardware divider to generate a reference clock for whatever purpose u need |
| dplatt@coop.radagast.org (Dave Platt): Mar 22 02:51PM -0700 In article <MPG.36ff177e8da2d6379899ac@news.east.earthlink.net>, >of 2 places right now, Bomar that last report was $ 50 per crystal and >minimum of $ 100 for an order. Another in England that is I think about >$ 30 per crystal. Those programmable-frequency oscillators may have distinctly worse phase-noise characteristics than a real crystal in a good oscillator circuit. They may not necessarily be suitable for communications projects or others that are sensitive to phase noise / jitter. |
| tabbypurr@gmail.com: Mar 22 03:49PM -0700 On Friday, 22 March 2019 21:45:47 UTC, bitrex wrote: > least one general-purpose integrated RC clock oscillator. > Appliances that use the 60Hz wall voltage for a timebase for anything > don't really exist anymore not even cheap digital alarm clocks. There is one appliance fwiw, the pin or segment timer. But portable generators & electrical precision are alien concepts. NT |
| Fox's Mercantile <jdangus@att.net>: Mar 22 05:57PM -0500 On 3/22/19 4:45 PM, bitrex wrote: > Why is frequency stability important in a consumer-grade generator? Obviously, you've never seen a ferro-resonant line conditioner set fire to itself because it was running on 60 Hz. This was a very real problem with remote radio sites, running on a generator with Motorola Micro stations. -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com |
| Ralph Mowery <rmowery28146@earthlink.net>: Mar 22 07:30PM -0400 In article <cIclE.40169$cR2.11500@fx22.iad>, user@example.net says... > least one general-purpose integrated RC clock oscillator. > Appliances that use the 60Hz wall voltage for a timebase for anything > don't really exist anymore not even cheap digital alarm clocks. Most home devices not counting clocks are not that frequency sensitive. The main thing is the simple generator must run close to 3600 rpm to generate the desired voltage which is also generated at 60 hz. A few cycles one way or the other does not mater, but the voltage might. |
| Ralph Mowery <rmowery28146@earthlink.net>: Mar 22 07:31PM -0400 In article <502gmf-3ne.ln1@coop.radagast.org>, dplatt@coop.radagast.org says... > phase-noise characteristics than a real crystal in a good oscillator > circuit. They may not necessarily be suitable for communications > projects or others that are sensitive to phase noise / jitter. They are 'dirty' compaired to a crystal. I have played with a couple on a spectrum analizer just to see. Probably not very useful if a clean signal is desired, but fine if just a close frequency is needed for things like a microprocessor clock. |
| Andy Burns <usenet@andyburns.uk>: Mar 22 07:06PM Oliver Wilson wrote: > My main confusion about the SATA 0 unknown is whether it's the 1TB disk > that's bad, or the RAID card that is bad. I think the message about SATA port0 is referring to a SATA port on the motherboard, not a SATA port on the RAID card. > I seem to see you saying that you think the 1TB drive is actually good? > Did I understand that correctly? One of your photos shows the RAID card saying that all four drives and all three arrays are good. > If the 1TB drive is likely good, then are you saying the RAID card is > likely bad? Hopefully it is good too, after all one of your photos does show the RAID card having detected the drives and saying the arrays are optimal. I would move the card back to the slot it was in, different PCIe slots can have different numbers of "lanes" and the PCIe training error you show is referring to the motherboard and PCIe card being unable to agree the correct number of lanes to use. |
| dplatt@coop.radagast.org (Dave Platt): Mar 22 01:03PM -0700 In article <gfkq2kFdf3bU1@mid.individual.net>, >> that's bad, or the RAID card that is bad. >I think the message about SATA port0 is referring to a SATA port on the >motherboard, not a SATA port on the RAID card. That's the way it looked to me, as well. The SATA ports and drives on the motherboard are normally handled by the motherboard chipset and the BIOS. The motherboard BIOS doesn't deal directly with the ports on the add-on card. These are the responsibility of the card's own on-board BIOS - the resulting drives/volumes are registered as drives, but not as "ports" per se. >can have different numbers of "lanes" and the PCIe training error you >show is referring to the motherboard and PCIe card being unable to agree >the correct number of lanes to use. Simply unplugging, and then re-seating a controller card can often be effective at resolving problems like this. Not always, but it sometimes works. Make sure that the card is properly seated in the slot, both when you first plug it in, and after you screw the card bracket to the case! I've seen plenty of situations in which a bent bracket, or a case having slots of a funny size, or a bit of obstruction at the bottom of the card slot where the bracket "finger" fits in, is enough to cause the act of "screwing down" the card to actually flex the card upwards a bit out of the PCI or PCIe slot. Even if it works OK at first, the card sometimes works its way upwards a bit further and the slot connection becomes intermittent. |
| Martin Gregorie <martin@mydomain.invalid>: Mar 22 08:29PM On Fri, 22 Mar 2019 12:19:02 -0400, Oliver Wilson wrote: > My main confusion about the SATA 0 unknown is whether it's the 1TB disk > that's bad, or the RAID card that is bad. Do you have, or can you get, a Linux system that you can use to check the disks? It might have a spare SATA connector you can connect the disk being tested to or, easier, you could use USB-connected disk dock that you can slot the disks being tested into. If so, try two tests, both to be run with the disk powered up but not mounted. - 1 (quick) run gparted to look at the disk partitioning. Are any errors reported? Does the partitioning scheme look sensible and is it the same on mirror disks? - 2 (slower) run "fsck -p" against each partition each disk. If any errors are reported, try using fsck to repair the failing partition(s). - 3 install smartd if it isn't already installed and use it to see how many hours each disk has run and what prefailure and/or failure indications each of them shows I've had good quality (Fujitsu and Western Digital) disks fail at around 40-50k hours and cheap consumer crap fail at 3000 hours. > I seem to see you saying that you think the 1TB drive is actually good? > Did I understand that correctly? If those tests show the disks are OK, THEN you should suspect the RAID controller. -- Martin | martin at Gregorie | gregorie dot org |
| Andy Burns <usenet@andyburns.uk>: Mar 22 08:42PM Martin Gregorie wrote: > Do you have, or can you get, a Linux system that you can use to check the > disks? If (some of) the disks have RAID metadata on them, be very careful attaching them to non-RAID SATA ports ... |
| Martin Gregorie <martin@mydomain.invalid>: Mar 22 10:03PM On Fri, 22 Mar 2019 20:42:13 +0000, Andy Burns wrote: >> the disks? > If (some of) the disks have RAID metadata on them, be very careful > attaching them to non-RAID SATA ports ... I don't 'do' RAID (never needed to outside RAID 1 on Tandem NonStop and Stratus fault tolerant systems, but apart from suggesting gparted or fsck repairs (WHICH THE OP CAN EASILY IGNORE), everything else I suggested is, or should be, read-only. How could read-only checks mess up RAID metadata? Colour me genuinely puzzled: an explanation would be appreciated. What I described (looking at what gparted, fsck and smartd have to say) is no more and no less that what I do routinely to hopefully spot failing disks before they break. -- Martin | martin at Gregorie | gregorie dot org |
| Andy Burns <usenet@andyburns.uk>: Mar 22 10:22PM Martin Gregorie wrote: > Stratus fault tolerant systems, but apart from suggesting gparted or fsck > repairs (WHICH THE OP CAN EASILY IGNORE), everything else I suggested is, > or should be, read-only. How could read-only checks mess up RAID metadata? read-only wouldn't, but an inexperienced user could accidentally write something, and if the disks are from a RAID system, the partitions probably don't start where partition tools are going to be looking for them, so you'll get a false sense that there aren't valid partitions on the disks. |
| Andy Burns <usenet@andyburns.uk>: Mar 22 10:31PM Andy Burns wrote: > if the disks are from a RAID system, the partitions > probably don't start where partition tools are going to be looking for > them, so you'll get a false sense that there aren't valid partitions on s/partitions/file-systems > the disks. Generally to inspect RAID disks that aren't attached to their RAID controller, you need special software, e.g. <https://www.osforensics.com/rebuild-raid.html> |
| Martin Gregorie <martin@mydomain.invalid>: Mar 22 10:33PM On Fri, 22 Mar 2019 22:31:07 +0000, Andy Burns wrote: > Generally to inspect RAID disks that aren't attached to their RAID > controller, you need special software, e.g. > <https://www.osforensics.com/rebuild-raid.html> OK, noted. Thanks. -- Martin | martin at Gregorie | gregorie dot org |
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