- 9v Batteries - 3 Updates
- Magnetron question - 18 Updates
- WD-40, CRC 'Lectra-Clean, Liquid Wrench, and Kroil - 4 Updates
| Mike <ham789@netscape.net>: Feb 13 12:48PM -0800 On 2/12/2019 10:12 PM, malua mada! wrote: >> If it's a little charger designed to charge these EBL batteries, >> you're good to go. If it ain't, don't use it. > bonai 9V 80 mA (x1) 50 mA (x2) charger. brought the patient up to 7.68 volts. which is what one has to accept for 9V these days? or anyhow below 8.4V from what you write. If you look here https://www.amazon.com/EBL-Rechargeable-Batteries-Battery-Charger/dp/B079G37Y61 you will see Battery: 6F22 9V 600mAh rechargeable li-ion batteries, note that all 9v li-ion batteries' full voltage is 8.4V You have the battery apart. What's the voltage on each individual cell? If it's not the same, make it so. |
| "malua mada!" <fritzo2ster@gmail.com>: Feb 13 09:01PM -0800 On Wednesday, February 13, 2019 at 12:48:23 PM UTC-8, Mike wrote: > You have the battery apart. What's the voltage on each individual cell? > If it's not the same, make it so. 3.823 3.826 :-) |
| Mike <ham789@netscape.net>: Feb 13 10:26PM -0800 On 2/13/2019 9:01 PM, malua mada! wrote: >> You have the battery apart. What's the voltage on each individual cell? >> If it's not the same, make it so. > 3.823 3.826 :-) That's gonna give you significantly reduced capacity. If it were me, I'd set up the bench supply to 8.2V with a 50mA current limit. Hook that to the battery and again measure the cell voltages while charging. That will give you an approximation to the internal resistance of the cells. Increased resistance will cause the BMT chip to shut off charging at a lower cell resting voltage. Let it charge and see if it gets to 8.2V without shutting off. They're rated at 8.4V, but I usually don't push 'em that hard. It's difficult to know exactly what chemistry is used, but lower voltage should improve cell life. Another possibility is that the charger is crap. It has to do some tests and make assumptions about which technology you're charging. It may be getting it wrong. |
| Fox's Mercantile <jdangus@att.net>: Feb 13 10:55AM -0600 On 2/13/19 10:36 AM, technowb wrote: > Do you know what would happen if the alternative is a wrong option? > Would I risk frying inverter module or something else? The primary issue would be how the microwaves get from the magnetron to the oven chamber. That's THE critical item. Physical match. A more obscure and unlikely problem would be the heater voltage to run the tube with. Then there's the little details. Does the HV supply exceed the tube ratings. Does the tube draw more current than than the HV supply can supply? -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Feb 13 10:06AM -0800 Much as I am not happy with needless landfill, nor with the tissue-paper economy that builds irreparable crap these days, there comes a time when it is best to simply dump the item rather than attempt to salvage it. Microwaves are one of those things. Given the very real safety issues raised by after-sales work on these devices, there is no particular reason to make such repairs unless the unit is otherwise special (perhaps a vintage Amana or similar, or an early built-in) or hideously expensive to replace. And, as Jeff suggests, a visit to any thrift-store will yield any number of options. That being written, our incumbent microwave is 10 years old, the one on our third floor followed us back from Saudi in 2005, and the one at our summer house is now seven (but gets little use). Peter Wieck Melrose Park, PA |
| technowb <pietrarca@gmail.com>: Feb 13 10:43AM -0800 Mr. Wieck don't you think this one falls into "hideously expensive to replace"? Given that a luxury microwave oven costs around 300€ and this one costs more than 700, I'd say it does.. :) there are almost no more expensive combi ovens in the market: other cheaper ovens I owned lasted 15 years and such. I would be happy to buy another one and avoid complications, but I cannot afford it, and I am trying to understand the implications of the choice to self-repair it. I know that there may be serious injuries ahead, that's why I am gathering informations here and there before taking any further step.. :) Thank you |
| John-Del <ohger1s@gmail.com>: Feb 13 11:02AM -0800 On Wednesday, February 13, 2019 at 1:43:38 PM UTC-5, technowb wrote: > I would be happy to buy another one and avoid complications, but I cannot afford it, and I am trying to understand the implications of the choice to self-repair it. > I know that there may be serious injuries ahead, that's why I am gathering informations here and there before taking any further step.. :) > Thank you Apparently (or should I say supposedly), this magnetron replaces the one in your unit: https://www.directrepair.eu/microwave-oven-2m236m42-00268142-panasonic.html About 100E with freight. Are you sure the magnetron is bad? A lot of things can prevent it from being powered up: door interlock switch, control board problem, burned relay (or connection - not uncommon on Whirlpools), HV diode or HV capacitor. |
| Ralph Mowery <rmowery28146@earthlink.net>: Feb 13 02:35PM -0500 In article <55fd66b1-d704-4427-843a-61a330c19522@googlegroups.com>, pietrarca@gmail.com says... > The official tech support said that I would need to buy a new one because they can't find the magnetron, but I cannot afford another expense of that kind - in particular for a product that can't be repaired after too little time.. > I think that unless I find the same exact magnetron I will go for the suggested alternative, at least It's worth a try. As that is an expensive microwave, you may be able to look around and find another inexpensive modle that uses the same tube. Maybe even in a recycle or thrift store for a used one. |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Feb 13 11:49AM -0800 On Wednesday, February 13, 2019 at 1:43:38 PM UTC-5, technowb wrote: > Mr. Wieck don't you think this one falls into "hideously expensive to replace"? OK - not knowing where you are, other than somewhere in Europe: https://www.europart.nl/whirlpool-magnetron-480120100525-mwf210w-amw834ix-oven-magnetron-92716700 Not so expensive, either. This part was used in a number of brands, from Jenn-Aire to Panasonic to Whirlpool, and others. So, attach the PN to other brands, it may pop up. Peter Wieck Melrose Park, PA |
| etpm@whidbey.com: Feb 13 12:15PM -0800 >I can tell you this. There are only a few types of magnetrons used in uWave ovens. If the mounting fits, 80%+ chance it works. The actual power is determined by the value of the cap and somewhat by the secondary of the transformer. >They can use a higher rated magnetron in a lower powered oven and they still save money by buying more of the same part. They save money on the transformer or the cap. >The mount has to REALLY match. Close is not good enough. So the reason microwave ovens cycle on and off at the lower power settings is because different caps would be needed for different power outputs? I always thought it was the tube itself, that it worked best at some certain power output. Eric |
| Mike <ham789@netscape.net>: Feb 13 01:11PM -0800 On 2/13/2019 10:43 AM, technowb wrote: > I would be happy to buy another one and avoid complications, but I cannot afford it, and I am trying to understand the implications of the choice to self-repair it. > I know that there may be serious injuries ahead, that's why I am gathering informations here and there before taking any further step.. :) > Thank you I haven't heard a convincing argument that the magnetron is the problem. How did you verify that? |
| tabbypurr@gmail.com: Feb 13 01:43PM -0800 > outputs? I always thought it was the tube itself, that it worked best > at some certain power output. > Eric Early 2 power level nukes used a capacitor & HV switch to reduce anode i. It's cheaper & more reliable to switch the power on & off. And safer. The only time it matters is with mousse. NT |
| etpm@whidbey.com: Feb 13 02:20PM -0800 >> Eric >Early 2 power level nukes used a capacitor & HV switch to reduce anode i. It's cheaper & more reliable to switch the power on & off. And safer. The only time it matters is with mousse. >NT Darn it! I was gonna try to make some mousse tonight in the microwave. Eric |
| technowb <pietrarca@gmail.com>: Feb 13 02:26PM -0800 @Mike I have no hard evidence about the magnetron being faulty, however this was the diagnosis made by the tech guy who came over to fix it. The whirlpool oven displays error F05 (which I was not able to find anywhere in my research over the internet). It displays it only when using features that relay on microwawes, other than that it works fine. The "official repair guide" - which I have not seen - seems to state that to fix error F05 it is needed to replace the inverter board and the magnetron. Since the tech guy had a spare new inverter board, he switched it and left it in the oven, unfortunately that didn't fix the error. That's the reason why I am assuming it's the faulty magnetron.. I am actually hoping that, trusting that the tech guy placed a working inverter board inside my oven. :) Thank you for your inputs, you're being really helpful |
| Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Feb 14 12:10AM +0100 On 13-2-2019 20:02, John-Del wrote: > Apparently (or should I say supposedly), this magnetron replaces the one in your unit: > https://www.directrepair.eu/microwave-oven-2m236m42-00268142-panasonic.html > About 100E with freight. Are you sure the magnetron is bad? A lot of things can prevent it from being powered up: door interlock switch, control board problem, burned relay (or connection - not uncommon on Whirlpools), HV diode or HV capacitor. Shop for a second hand one of the same age/power range, and swap components. |
| Ralph Mowery <rmowery28146@earthlink.net>: Feb 13 06:40PM -0500 In article <5c64a3f5$0$31762$e4fe514c@textnews.kpn.nl>, burrynulnulfour@ppllaanneett.nnll says... > Shop for a second hand one of the same age/power range, and swap components. Sometimes that is the only way to repair items. I do not like built in items for that reason. Or even fancey (expensive) items to do simple tasks. I really hate the cars that give you almost no options as to what you want. Last car had to have leather seats if I wanted a V6 engine. I hate the leather. Makes me sweat in the summer and cold in the winter before the heated seats warm up. Had the 'moon roof' no need at all for that as far as I am concerned. About 10 years ago I bought a house and the only reasonable place for the refrigerator is a small opening. That ment I was limiated in the height and especially the width of a unit I could use unless modifications to the cabinet were made. |
| jurb6006@gmail.com: Feb 13 04:10PM -0800 >"IE: Instead of heating something for the typical one minute at full power, heating it for two minutes at half power(or even medium high or 60% if such setting available)? That way the magnetron cycles on and off instead of running constantly, and also the food is more evenly heated. " No. It is doing the same work AND being thermally cycled. Now had you an older one where they put more than six bucks into it, they had a lower tap on the transformer for the lower power setting. One of those maybe. With that, lower power might just make the tube last longer. Not by cycling on and off for a longer time. |
| jurb6006@gmail.com: Feb 13 04:20PM -0800 >"I suspect magnetrons are the same way. " It seems CRTs are. I had a Zenith 20" come in, had the best picture I ever saw on that model because the tube was strong. I mean STRONG. Te complaint was there was a slight noise when it was turned off. I discovered that it really wasn't turning off, when the micro said power off it muted the audio and video but the HV, and of course the filament of the CRT and all that was still on. I told them not to fix it. Management didn't agree so it got fixed. We knew for a long time about CRTs, like NEC bigscreens had active all the time AKB and when you first turned them on they were actually "cathode stripping". Sony's AKB had a delay until beam current was normalized, as told by the AKB circuit. Didn't help, their CRTs were junk by then. But I got this 35 year old Sony in my room with about the best god damn picture you ever saw, and it is never shut off. To shut it up I just switch to a dead source. You will NOT see color like on this thing. Anyway, the magnetron has a filament so when it cycles on and off the filament thermally cycles and in almost ANYTHING in the physical world thermal cycling is bad. The old microwaves with the tap, the filament voltage was still the same. Actually if you look at the power level switch on one of them you can see it is made to switch a few thousand volts. It is not a simple slide switch. |
| thekmanrocks@gmail.com: Feb 13 05:00PM -0800 For my GE micro, power level cycling is as follows: HI/Full - Magnetron on continuously 90% - On 27sec, off 3sec 80% - On 24sec, off 6sec. etc etc. 50%/Medium - On 15sec, off 15sec 20%/Lowish - On 6sec, off 24sec And so on. I'm sure the designers took everything into account when providing for all those power levels. I almost never use Full, except for when boiling water. |
| Fox's Mercantile <jdangus@att.net>: Feb 13 07:16PM -0600 > But I got this 35 year old Sony in my room with about the > best god damn picture you ever saw, and it is never shut > off. Which of course, is entirely relevant to magnetrons. -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com |
| Mike <ham789@netscape.net>: Feb 13 05:39PM -0800 >>> at some certain power output. >>> Eric >> Early 2 power level nukes used a capacitor & HV switch to reduce anode i. It's cheaper & more reliable to switch the power on & off. And safer. The only time it matters is with mousse. Try cooking an egg to dispel that thought. Older microwaves had minimum on-time because of the filament warm up time...and the lack of high voltage power supply electronics back then. A 10-second on-time is plenty of time for localized heating to cause food to explode. The newer inverter microwaves have much shorter on-times so food doesn't explode as easily even at the same average power. >> NT > Darn it! I was gonna try to make some mousse tonight in the microwave. > Eric Under what conditions did the microwave fail? Did it quit while in use? Between uses? Any power outages or lightning storms in between? I've never fixed a newer microwave. All my repairs were diode replacements in older machines. I don't think I'd even try to fix my Panasonic inverter without a full set of schematics. Even then, all the sensors would be a nightmare to reverse-engineer. I'm gonna make some guesses. I doubt that the magnetron has failed. Sure, it can crack if you overheatd it by running it for long periods nearly empty. More likely something else failed. There's not much to cause instant failure of a magnetron if you didn't overheat it. I doubt that there are any high voltage components on the controller that was replaced. The oven is full of sensors for safety and cook control. Any of them can cause the system to inhibit the microwave function. I'd guess that the only things a controller would monitor might be power supply voltage and temperature. Just not worth the expense to do more. But there's plenty more to go wrong. Here's some reading material. https://www.thermex-thermatron.com/wp-content/uploads/2015/11/FailureOfMagnetrons_v3.pdf https://www.repairfaq.org/sam/micfaq.htm |
| etpm@whidbey.com: Feb 13 11:45AM -0800 On Tue, 12 Feb 2019 22:24:11 -0600, Fox's Mercantile <jdangus@att.net> wrote: >> "Which Penetrating Oil is Best? Let's find out!" >> <https://www.youtube.com/watch?v=xUEob2oAKVs> >I've seen this before, I serious question his results. I'm starting to think that penetrating oils don't help much with the initial torque required to break a fastener loose. But once even a little movement happens the oil can then act as a lubricant and help prevent galling as the fasteners are turned. But I am not convinced because of one particular case. An antique rifle of mine has a flip up peep sight. The peep sight can be adjusted by turning a knurled collar. When I got the rifle it was obvious that the collar was stuck pretty good because there was damage to the knurl from pliers. I tried various penetrating oil over the years and could never get the collar to trurn. Then a few years ago I tried using some Break Free on the thing. I wet the assembly in the evening and the next morning I was able to turn the collar with just my fingers. Not easily at first. But I was able to get the thing apart and it was rust that washed out of the collar and off of the screw. Eric |
| Ralph Mowery <rmowery28146@earthlink.net>: Feb 13 04:38PM -0500 In article <dks86e9vhjl07vetlij6f22dnqs9jkksbt@4ax.com>, etpm@whidbey.com says... > easily at first. But I was able to get the thing apart and it was > rust that washed out of the collar and off of the screw. > Eric Waiting overnight or even 2 or so days making sure the part stay wet often works very well. Many will spray the part and expect it to be free in about 10 seconds. |
| etpm@whidbey.com: Feb 13 02:16PM -0800 On Wed, 13 Feb 2019 16:38:51 -0500, Ralph Mowery >Waiting overnight or even 2 or so days making sure the part stay wet >often works very well. Many will spray the part and expect it to be >free in about 10 seconds. I know about the waiting bit. I had tried that several times on the sight. Then gave up for years. Then tried the Break Free stuff. I'm not sure why it wouked when nothing else did. Eric |
| Terry Schwartz <tschw10117@aol.com>: Feb 13 03:22PM -0800 I've always had reasonable success heating the part, then as it cools applying PB Blaster. Time. Then applying mechanical impact -- that seems to be the trifecta. A few taps with a hammer, or an impact wrench, or the back of a crescent wrench, almost without fail will loosen the suspect nut or bolt. |
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