[Amps] Measuring RF Power

[R.Measures]

On Mar 23, 2005, at 9:52 AM, Gary Schafer wrote:

>
>
> R. Measures wrote:
>> On Mar 22, 2005, at 2:53 PM, Gary Schafer wrote:
>>> When adding PEP to the mix it is vital that average power be 
>>> understood
>>> properly. Best to put RMS power out of mind as it is good for nothing
>>> but confusion.
>>>
>>> Reading the FCC definition of PEP it goes something like:
>>> Peak envelope power is the AVERAGE power in one RF cycle at the 
>>> crest of
>>> the modulation envelope.
>>>
>>> That means if you transmit a 1500 watt average power cw signal, your 
>>> PEP
>>> is also 1500 watts. If your peaks hit 1500 watts on voice your pep is
>>> 1500 watts.
>>>
>>> Imagine the confusion trying to figure that out if you called the 
>>> 1500
>>> watt cw signal RMS power!
>> How many watts of heat would a key-down 1500w RMS  CW signal produce 
>> in a R?
>
> If it were 1500 watts average power cw signal it would produce 1500 
> watts heat in the R.
>
> I don't know what you would do with 1500 watts RMS.

Calculate P by measuring the peak-V with a NBS traceable o'scope, 
square E-pk, divide that by 2 x R and use it to calibrate a wattmeter.
>
> 73
> Gary  K4FMX
>
>>>
>>> 73
>>> Gary  K4FMX
>
>> Richard L. Measures, AG6K, 805.386.3734.  www.somis.org
>
>
>
>
>

Richard L. Measures, AG6K, 805.386.3734.  www.somis.org