Larry says:
>So even with many hundreds of dollars spent on new purchases, many
>thousands of dollars worth of my own test equipment, all the resources of
>my lab at work, I don't know for sure if my power out is 1300 or 1500 or
>1700 watts.
If you are an approved type testing laboratory, your typical conducted power
measurement to a 95% confidence level is +/-0.75dB. That's 1262 to 1782 watts.
Larry, you got any buddies at NIST who can calibrate a power meter at the 1500
watt level to reduce errors in couplers etc?
You might get better accuracy using a liquid cooled load, measuring inlet and
outlet temperatures with a constant head apparatus to maintain constant coolant
flow, and then running a substitution with DC. If you keep the ambient
temperature constant (I guess that's the amp in a different room to the air
conditioned room in which the load is) I guess you may be able to get to about
+/-0.4dB - maybe a bit better. Provided the amp is rated for key down operation
for the length of time taken to achieve thermal equilibrium. That'll be +/-
about 140 watts.
Worrying, this measurement accuracy business, isn't it?
73
Peter G3RZP
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