Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > sci.physics > #565776

Re: Can you call a cell phone in the microwave?

Show all headers | View raw

benj <none@gmail.com> wrote:
> On 03/26/2016 12:39 AM, isw wrote:

<snip>

>> If evanescent wave attenuation works so well, why are the obviously more
>> expensive choke joints used almost universally on waveguides?
> 
> Because the purpose of the choke in a guide is to allow the energy to go 
> DOWN the guide without loss at joints. In a door the purpose of the seal 
> is to keep energy from leaking out at dangerous levels. Since the 
> microwave has lots of power if a little energy is lost in evanescent 
> waves (by definition lossy) it makes no difference. The point is you 
> don't want the radiation out where people will have their hands etc. So 
> long as the gap is small there is no problem. This is why there is a 
> switch on the door that turns off the oven if someone tries to close the 
> door on a towel or something that widens the gap. User manual usually 
> warns about keeping door gap clean, free of food, or corrosion etc.

Microwave ovens have lots of power compared to cell phones, but that is
about it.

Consumer microwave ovens typically run from about 500 W to 1 kW.

The smallest radar I ever worked on was 5 kW and most where in the
hundreds of kilowatt range with some well over 10 MW.
 
It is in such equipment where standardized, choke jointed waveguide is
used.


-- 
Jim Pennino

Back to sci.physics | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Can you call a cell phone in the microwave? Sam Wormley <swormley1@gmail.com> - 2016-03-22 15:16 -0500
  Re: Can you call a cell phone in the microwave? jimp@specsol.spam.sux.com - 2016-03-22 20:57 +0000
    Re: Can you call a cell phone in the microwave? isw <isw@witzend.com> - 2016-03-22 21:50 -0700
      Re: Can you call a cell phone in the microwave? john <johnsefton288@gmail.com> - 2016-03-23 07:04 -0700
  Re: Can you call a cell phone in the microwave? Sergio <invalid@invalid.com> - 2016-03-22 16:43 -0500
    Re: Can you call a cell phone in the microwave? Poutnik <poutnik4nntp@gmail.com> - 2016-03-23 05:37 +0100
      Re: Can you call a cell phone in the microwave? Sergio <invalid@invalid.com> - 2016-03-23 11:11 -0500
      Re: Can you call a cell phone in the microwave? isw <isw@witzend.com> - 2016-03-23 21:05 -0700
        Re: Can you call a cell phone in the microwave? jimp@specsol.spam.sux.com - 2016-03-24 06:17 +0000
          Re: Can you call a cell phone in the microwave? benj <none@gmail.com> - 2016-03-24 10:55 -0400
            Re: Can you call a cell phone in the microwave? jimp@specsol.spam.sux.com - 2016-03-24 19:17 +0000
          Re: Can you call a cell phone in the microwave? john <johnsefton288@gmail.com> - 2016-03-24 08:22 -0700
            Re: Can you call a cell phone in the microwave? Sergio <invalid@invalid.com> - 2016-03-24 16:06 -0500
              Re: Can you call a cell phone in the microwave? john <johnsefton288@gmail.com> - 2016-03-25 05:49 -0700
                Re: Can you call a cell phone in the microwave? benj <none@gmail.com> - 2016-03-25 13:47 -0400
                Re: Can you call a cell phone in the microwave? Sergio <invalid@invalid.com> - 2016-03-26 21:23 -0500
                Re: Can you call a cell phone in the microwave? Virgil <VIRGIL@VIRGIL.com> - 2016-03-27 00:13 -0600
                Re: Can you call a cell phone in the microwave? john <johnsefton288@gmail.com> - 2016-03-27 05:32 -0700
            Re: Can you call a cell phone in the microwave? HVAC <mr.hvac@gmail.com> - 2016-03-25 11:40 -0700
          Re: Can you call a cell phone in the microwave? isw <isw@witzend.com> - 2016-03-24 22:55 -0700
            Re: Can you call a cell phone in the microwave? benj <none@gmail.com> - 2016-03-25 05:18 -0400
              Re: Can you call a cell phone in the microwave? jimp@specsol.spam.sux.com - 2016-03-25 18:11 +0000
              Re: Can you call a cell phone in the microwave? isw <isw@witzend.com> - 2016-03-25 21:39 -0700
                Re: Can you call a cell phone in the microwave? jimp@specsol.spam.sux.com - 2016-03-26 05:08 +0000
                Re: Can you call a cell phone in the microwave? benj <none@gmail.com> - 2016-03-26 01:57 -0400
                Re: Can you call a cell phone in the microwave? jimp@specsol.spam.sux.com - 2016-03-26 17:57 +0000
            Re: Can you call a cell phone in the microwave? jimp@specsol.spam.sux.com - 2016-03-25 18:10 +0000
  Re: Can you call a cell phone in the microwave? James McGinn <jimmcginn9@gmail.com> - 2016-03-29 21:31 -0700

csiph-web