[time-nuts] 4 KV Power Supply Recommendations
Lux, Jim (337C)
james.p.lux at jpl.nasa.gov
Tue Jan 19 00:13:15 UTC 2010
On 1/18/10 2:10 PM, "Didier Juges" <didier at cox.net> wrote:
> I could not resist, so I checked my relatively expensive Sears/Kenmore
> microwave oven.
> The results are there:
> http://www.ko4bb.com/Test_Equipment/Microwave_oven_leakage/
>
> In one word, dismal. Almost 1W peak power leakage at 1 foot, and almost
> 100MHz occupied bandwidth.
>
> I looked with a crystal detector driving a scope, and it is obvious the unit
> is driven from a 60Hz transformer with half wave rectification, and has no
> filtering whatsoever, like the first Microwave oven I have ever opened (a 20
> years old model long dead).
>
>
The cost of more expensive models is in the nice trim, control features,
integrated vent hood, etc. They all use basically the same wiring diagram:
a transformer with a lot of leakage inductance, a diode, a capacitor, and
the magnetron. A higher power oven will have a bigger transformer and tube.
The leakage standard is 2 mW/cm^2. A watt into your sensor indicates
either a bad seal on the oven or some other measurement error.
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