Correct, microwave ovens have, in series, several safety interlock switching devices that control the HV transformer. But opening the door prior to the set time-out will not immediately de-energize the magnetron; that is, the delay is programmatic, not electro-mechanical.
Brian -----Original Message----- From: Ken Javor [mailto:[email protected]] Sent: Thursday, May 14, 2015 4:26 PM To: [email protected] Subject: Re: [PSES] Interference Caused by Microwave Oven Newsworthy indeed, but hardly something to self-promote through publication! And I would think that the interlock would interrupt magnetron operation as soon as the latching mechanism was depressed, which is before the door actually even begins to open, so that the gasket should still be making the seal. Ken Javor Phone: (256) 650-5261 > From: CR <[email protected]> > Reply-To: <[email protected]> > Date: Thu, 14 May 2015 19:21:42 -0400 > To: <[email protected]> > Subject: Re: [PSES] Interference Caused by Microwave Oven > > On 5/14/2015 6:58 PM, Ken Javor wrote: >> why doesn¹t the rf shut off when the door is opened? And a second >> one: why was it deemed worthy of publishing an article that a >> microwave oven interfered with data collection since 1988? > > It does, but probably not instantly. Just guessing, but ... A magnetron > is a thermal diode that can continue to generate RF as long as there's > enough emission, and enough voltage to move electrons past its cavity > resonators. The door uses a choke joint to prevent RF from escaping, and > as that's being opened, it can radiate. And it's newsworthy because > people smart enough to run a radio telescope should be smart enough to > run down something like this. IMO! > > Cortland Richmond > KA5S > (semi) retired from EMC engineering - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
