| micky <NONONOmisc07@bigfoot.com>: Dec 03 04:11PM -0500 In sci.electronics.repair, on Wed, 30 Nov 2016 23:25:52 -0800, Jeff >>Stick an old CD in the MW and you can see exactly when the RF power starts. >Good idea. Another way would be to cram a wad of paper between the >door and the oven, and use a microwave leakage detector to measure the You can really do that? I did do that with Amana model 2, that had no door latches, only springs. To check if the microwave detector was working, and it was. And to check if the oven was leaking and it wasn't. BTW, Radio Shack stopped selling its cheap detector years ago. I suppose it was sold by someone else but I haven't seen it. |
| micky <NONONOmisc07@bigfoot.com>: Dec 03 04:13PM -0500 In sci.electronics.repair, on Sat, 3 Dec 2016 03:08:33 -0800 (PST), >> > Jon >> Stick an old CD in the MW and you can see exactly when the RF power starts. >I tried that with one of my wife's Kenny G CDs. A few seconds in the MW improved it immensely. I have a 45 rpm record someone must have left in the sun. Seen from the side, it's one long sine wave, going around in a circle, and the amplitude is an inch and half. I'm trying to find a record player with a 2-inch needle so I can play it. |
| micky <NONONOmisc07@bigfoot.com>: Dec 03 04:14PM -0500 In sci.electronics.repair, on Fri, 2 Dec 2016 16:22:34 -0500, Tekkie® >> The ovens power output is also >> an important factor to consider. >Get a Binford 6150 MMMMM More power. All my power tools are Binford. |
| Jeff Liebermann <jeffl@cruzio.com>: Dec 03 04:06PM -0800 On Sat, 03 Dec 2016 16:11:12 -0500, micky <NONONOmisc07@bigfoot.com> wrote: >door latches, only springs. To check if the microwave detector was >working, and it was. And to check if the oven was leaking and it >wasn't. Yep, although the choke joint does a good job of blocking RF even with a gap. I just crammed a few layers of paper into the door of my Panasonic Sensor 1300U microwave oven. For a leakage detector, I used an MD-2000 detector. <https://www.google.com/search?tbm=isch&q=md-2000+microwave> and a Micronta (Radio Shock) 22-2001: <http://www.radiomuseum.org/r/radio_shac_micronta_microwave_leaka.html> With about 1/32" wad of paper, and with me shoving my weight against the door hold it closed, I got about a 5mw/cm^2 indication. There was also a cup of water inside the oven. The first time I ran it, it too about 5 seconds for the power to level off. Repeated tests took less, down to about 2 seconds. Note that the Panasonic oven uses "inverter technology" which might have different characteristics than a conventional microwave oven: <http://www.sears.com/articles/appliances/microwaves/what-is-inverter-technology.html> The Micronta 22-2001 meter isn't calibrated, but I assume that mid-scale is 5mw/cm^2, which is considered the danger level. I had to play with the orientation for maximum indication, but it read about 2/3 of way up the green part of the scale, and did not go into the red. Timing was about the same as the MD-2000 at about 3-5 seconds to reach full power. The first time I did the wad of paper in the door test was many years ago on a different microwave oven. The reading was much higher and the door had a machanical latch. How much higher, I don't recall. There are plenty of more modern leakage detectors available. <https://www.google.com/search?q=microwave+oven+leakage+meter&tbm=isch> I suspect I could get some RF to leak out of the oven by taking a length of coaxial cable, strip off 1/4 wavelength (31.3mm) from both ends, stuff one end in the oven, and measure whatever is re-radiated from the other end. >BTW, Radio Shack stopped selling its cheap detector years ago. I >suppose it was sold by someone else but I haven't seen it. No loss. -- 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 |
| micky <NONONOmisc07@bigfoot.com>: Dec 03 04:37PM -0500 In sci.electronics.repair, on Thu, 01 Dec 2016 04:02:02 -0600, >much money or a lot of time on this project, but they work fine othewise >so I want to fix them. >By the way, is there a name for this type of plug? At hamfests over the last 4 years, I think it's more than one person who has been selling a little transparent bag of 7 power plugs, all different, and I those 7 make up 99% of all the plugs used. At hamfests one bag was only $2 so I bought 3 on the theory I'd need 3, all the same size. But that doesn't mean you'll be able to find this. You very often see more than one vendor at more than one hamfest in more than one state selling the same stuff, but how often that happens nationwide, or where you and I are, I don't know. And a lot of hamfests are so small no one is selling this. This is no good because it's $30. FWIW the plugs are longer than my $2 set. :-) https://www.amazon.com/Generic-Straight-Universal-Connector-Notebook/dp/B00DC1PCJ8 This is $6 plus shipping: https://www.altex.com/6-Power-Cable-with-Assorted-Coax-Plugs-48-400-P143451.aspx A more likely bet and something always available online is that there are also universal power adapters, that have a range of voltages from 3 or 4.5 up to 9 or 12, and they have SEVEN or so power plugs on the end all attached at once. Make sure you get one with enough power for yoru speakers because they come in 500ma and 1000mamp iirc. Even the big one is no more than $10. I have 3 or 4 universal ones of various ratings and I use them to figure out the minimum voltage I need to make something work, if it's not labeled, and to use temporarily until I find or make a one-size adapter. But sometimes temporarily drags on for years, like for my router. I used a universal temporarily until I found an exact replacement on ebay. That worked for a year or two before it burned out in the same way the first one did. Someone, maybe here, said they were known to be unreliable. 5 minutes after the second one broke, I was back to the universal, which was still lying on my desk behind the monitor. Make sure the voltage and amperage goes high enough. $18 for 1300 ma but you can probably do better https://www.amazon.com/PowerLine-90367-Universal-Power-Adapter/dp/B00CWR39TI I hate to push walmart but this at least looks like the same thign, $13 https://www.walmart.com/ip/Original-Power-Powerline-1300-mA-Universal-AC-Adapter/16778839 Microcenter has more than one model, not especially cheap. FINALLY THIS is what I meant $8.35 http://www.ebay.com/itm/AC-DC-Wall-Power-Charger-ADAPTER-Universal-3-4-5-6-7-5-9-12V-Power-supply-2-5A-/301595192644?hash=item4638796d44:g:ROkAAOSwv0tVLb2D Well I like the ones where they are all wired in at the same time, including to replace a 9-volt battery, but maybe you don't care. |
| You received this digest because you're subscribed to updates for this group. You can change your settings on the group membership page. To unsubscribe from this group and stop receiving emails from it send an email to sci.electronics.repair+unsubscribe@googlegroups.com. |
No Response to "Digest for sci.electronics.repair@googlegroups.com - 5 updates in 2 topics"
Post a Comment