[Elecraft] Measuring SSB RMS Power

[Bob McGraw K4TAX]

To evaluate speech use a pink noise source.  That is the standard source signal for acoustic measurements. 

Bob, K4TAX


Sent from my iPhone

> On Jun 20, 2019, at 10:34 AM, John Oppenheimer <john at kn5l.net> wrote:
> 
> Hi Don,
> 
>> On 6/20/19 9:21 AM, Don Wilhelm wrote:
>> John,
>> 
>> That connection is OK if you realize that your scope is reading the DC 
>> voltage developed by rectifying the RF from 1/2 of the load.  You still 
>> have to use the power formula that is in the DL1 manual.
> 
> Well yes, power references are DCV^2 / 25
> 
> DdB ratios computed using voltage ratios in the form of
> 20 * Log(v1/v2). For example, 0 compression Pep/Pav dB =
> 20 * log(15.3/5.24) = 9.3. I do need to flip the table title to Pav/Pep
> for proper negative dB values, Done.
> 
>> I prefer to allow the 'scope to read the full peak RF voltage.  Connect 
>> the 'scope probe to the side of one resistor which is connected to the 
>> BNC jack (one of the leads closest to the BNC), and the 'scope ground 
>> probe to one or the resistor leads furthermost away from from the BNC jack.
> 
> Using detected RF envelope for oscilloscope average RF measurement at
> each digitized point during long, six second, trace. This will result
> with increased accuracy when measuring modulated speech.
> 
> John KN5L
> 
>>> On 6/20/2019 9:38 AM, John Oppenheimer wrote:
>>> Using DL1 with Oscilloscope to measure KX3 SSB RMS power:
>>> 
>>> https://www.kn5l.net/ssbpower/
>>> 
>>> Question, is this technique correct?
>>> 
>> 
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