I agree, Jim, but if that were the case you would expect that it wouldn't matter whether Joe held a metal tray near the set-top box, since the antenna is on the roof. Sean On Tue, Oct 12, 2010 at 3:38 PM, wrote: > > =A0Sean, > > =A0If the RF field strength is high enough, it can overpower the frontend > of the RF chain in the satellite > =A0receiver, regardless of whether it is at the actual operating frequenc= y > or not. > > =A0Regards, > > =A0Jim > >> -------- Original Message -------- >> Subject: Re: [OT] Radiation from microwave oven >> From: Sean Breheny >> Date: Tue, October 12, 2010 2:18 pm >> To: "Microcontroller discussion list - Public." >> >> >> Yes, but the equipment which the OP is having trouble with is NOT wifi >> but rather a satellite TV receiver which does not operate at 2.4GHz. >> Moreover, the interference doesn't seem to be entering through the >> antenna (which is on the roof) or through the power line but by direct >> line of sight from the microwave since he can stop the interference by >> simply holding a metal sheet between the oven and the set-top box. >> >> I am not surprised that a microwave would interfere with 2.4GHz wifi - >> the oven is allowed to radiate a few 100 mW I think, so that would >> overpower the majority of wifi cards/routers and even access points. I >> am surprised, though, that 100mW or even 1W would be enough to >> interfere with a device operating on a different frequency band and >> whose antenna is not the entry point for the interference. >> >> Joe (OP), have you tried holding that metal shielding plate at various >> distances from the microwave but along the =A0line of sight? It would be >> interesting to see if it still prevents the interference when you are >> holding it near the microwave oven instead of near the set-top box. >> >> Sean >> >> >> On Tue, Oct 12, 2010 at 1:34 PM, Marcel Duchamp >> wrote: >> > On 10/11/2010 11:48 PM, Sean Breheny wrote: >> >> >> >> Am I correct that all of the RF connections to the set top box are >> >> shielded cable? If so, this seems a bit scary - I wouldn't think that >> >> the box should be susceptible to such a small signal as can leak out >> >> of a properly-shielded microwave oven. Even if the IF input were righ= t >> >> at 2.4GHz, there should be a continuous shield from the LNB to the se= t >> >> top box and it should take significant power to inject through this >> >> shielding. >> >> >> > >> > Where I work, the microwave oven would frequently knock out our 2.4 gi= g >> > wireless lan network. =A0It made me wonder the same thing... >> > -- >> > http://www.piclist.com PIC/SX FAQ & list archive >> > View/change your membership options at >> > http://mailman.mit.edu/mailman/listinfo/piclist >> > >> >> -- >> http://www.piclist.com PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist > > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .