[Amps] Advice needed for SS amp

[Manfred Mornhinweg]

Larry, Jim,

> Any one want to check my math?

I checked it, and Larry is right.

A half gallon of water (1893 milliliters), which has a specific heat of 
roughly 4.19 joule per milliliter per kelvin (the actual value varies 
slightly with temperature), heated for 5 minutes (300 seconds) with 1500 
watts, would warm up by

1500 * 300 / 1893 / 4.19 = 56.7 kelvin,

which is the same as 56.7 degrees Celsius. Hardly enough to make it 
boil, unless it was pretty warm to begin with!

Starting from typical tap temperature, and considering some loss that 
ends up heating the kettle and producing some steam, the actual time 
required for boiling would be somewhat between 7 and 8 minutes, assuming 
the power is actually 1500 W and the water volume is actually half a 
gallon - and that the water is pure, not mixed with some liquid that has 
a lower specific heat! Now I don't think that anyone will boil a 
water/glycol mix to make coffee, but it's very possible that the heater 
actually is consuming more than 1500 W, or that the amount of water is 
somewhat less than half a gallon.

This illustrates that cooling a legal limit amp with a bucket of water 
under the operating desk is a satisfactory method for casual operation 
in SSB, but won't cut it for a full weekend of RTTY contesting!

Manfred

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