>If you've lately tried to buy an Air Compressor you'll find
>that the current crop can now do the impossible and generate more
>horsepower than the circuit breaker can pass in the form of current.

>One of the large Department Store Chains started a new way of measuring
>horsepower a while ago and now it's the norm.

> this capacitor start motor will draw for a few cycles on
>startup well beyond the rated current and before the slow blow circuit
>breaker pops and that's how you get a 5HP 115VAC air compressor.

I should have come to you guys originally... :)

This is right in line with one of my current favorites.  Computer
speakers.   I was tearing apart one such specimen and after
laughing about the 80W rating on the box, just for fun I tried
the disreputable technique of multiplying the open-circuit
power supply voltage times the theoretical short-circuit
current through the collector resistor (asuuming a 0-ohm
transistor) and the most I could get was 2-3 watts.

Now, in the 70's the equally respectable game evolved like this:
Take an amplifier with a  12.5 watt rms output.   Well, we
all know that to get from rms power to peak power we can multiply
by 1.4 so now it's a 17.5 W amp.   The next guy say,s "well,
there's peak, and then there's peak-to-peak, so really we have
to double that and it's a 35 W amp.  Finally, it's a Stereo
amp so you've got TWO channels...70 W.  And that's before the
salesmen even got their hands on the specs.    Next came the
Institute of High Fidelity, to give it that official veneer and
relieve us of the necessity of actually verifying any parameters.
I don't know if they're still around, but the generic term
"peak music power" also caught on.

I ignored all this until recently (with those 80-watt desktop
jobs) but the other day I saw an ad for a complete computer
system and one of the little extras was a 1000W speaker
system.   As in kilowatt.  I think it's time to discuss
this a little :)

By the way, I got suspicious with the 80-watters because the
audio connector had only two wires.  The innards contained ONE
three-transistor amp, with the pair of speakers wired in SERIES.
No wonder the balance control on the computer seemed funny...


Barry

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