[AMPS] Power Handling of Resistors

Tom Rauch W8JI@contesting.com
Tue, 7 Mar 2000 09:08:19 -0500


Hi Jon,

> For that matter, I've not thought this through, but how many RF cycles at
> VHF could take place in a matter of a few milliseconds?  I guess you'd
> need to calculate the period, which is 1/F.  At 144 MHz, this is 6.9
> nano-seconds.  So if our event is on the order of nanoseconds you could
> get just a couple of RF cycles going which ain't gonna hurt anything.  The
> point is that a short event as Rich claims is what happens isn't going to
> stress components beyond a breaking point especially when it is so short
> it doesn't even show up on the meter movements.
> 
> At least that's the way I see it.

I used a five watt MOX resistor as a dummy load for a medical 
pulse generator test fixture, and the generator ran 1200 watts of 
pulse output with  65 uS pulses and a 0.1 percent duty cycle.

Even after weeks of operating, the resistor remained at 49.9 ohms.

Imagine how many photonic-parasitic-breakouts that would have 
been!



 
73, Tom W8JI
w8ji@contesting.com

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