[Elecraft] KPA1500 Linearity

[Fred Jensen]

Most, if not all analog measurement devices are spec'd at % of full 
scale which can lead to high absolute variances if the levels being 
measured are significantly below full scale.  A Bird with a 100W slug 
accurate to 10% of full scale [+/- 5W] would be within spec if it 
indicated a real 10 W signal at 5 W.  Many folks would say, "My K2/10 
will only produce half the power it should."  Most digital measurements 
involve processing circuitry/computation, again which can introduce 
errors in the lower end of a range, and be dependent on frequency as well.

Mathematics can be hard.  Arithmetic can be tricky. [:-)

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 6/19/2018 3:25 PM, John Oppenheimer wrote:
> Hi Scott,
>
> I wonder how the linearity of the two power meters was evaluated?
>
> Some years ago I checked the K3 and KX3 power meter against two other
> meters. They were just within 10%
> http://www.kn5l.net/Elecraft/Power.html
>
> John KN5L
>
> On 06/19/2018 04:56 PM, K9MA wrote:
>> I just repeated the linearity measurements, on both 40 and 15 meters.  I
>> used the KPA1500 meter to measure output, and the K3 power setting for
>> input.
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Elecraft at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to k6dgw at foothill.net