[AMPS] Re: Power Handling of Resistors

[Jon Ogden]

on 3/9/00 9:36 PM, Carl Clawson at cclawson@transport.com wrote:

>> Yet 256 Joules will destroy a tank circuit according to what you say.
> 
> It takes about 500 J to melt a gram of brass from room temperature. I think
> 256 would be enough to seriously damage a band switch. The unresolved
> problem isn't the available energy, it's how it gets to the switch.

Let's do the math:

A Joule is 1 Watt-second.  Multiply watts times seconds.  If I am
transmitting at 1500 Watts for 10 seconds, the total energy passing through
the switch is 15,000 joules.

So if I can pass 1500 watts safely through the bandswitch for 10 seconds (or
rather an indefinite period of time) then how would 250 Joules destroy it?

I don't doubt that it takes 500 Joules to melt brass.  But for how long a
period of time does one need to apply the energy to make it melt?

Perhaps I am incorrect in my understanding of the term "Joule" but when I
looked it up, it is by definition a watt-second.

Enlighten me.

73,

Jon
KE9NA

-------------------------------------
Jon Ogden
KE9NA

Member:  ARRL, AMSAT, DXCC, NRA

http://www.qsl.net/ke9na

"A life lived in fear is a life half lived."


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