[Elecraft] S meter differences from K3 to P3

[Fred Jensen]

On 10/13/2013 6:22 PM, Jack Berry wrote:
> When operating I see a big difference between the noise floor and
> signal indications between the K3 meter and P3 display. For instance,
> on 80 meters tonight I see a noise floor of around S2-3 on the P3 and
> a signal peaking just over S9.
>
> At the same time the K3 meter is displaying a noise level of S9 and a
> signal level of 20 over S9.
>
> Is that a calibration error, a result of settings that I have
> selected - or just the way things are?

Well Jack, it could be a calibration error, but

1.  Do you have the "K3 IF output" mod installed.  It's one resistor, 
and it raises the 8MHz IF output to the P3.

2.  I calibrated my S-Meter with my service monitor, S9 for 50uv in. 
Then I adjusted the P3 gain to give me -73dBm on the screen.

3.  The P3 averages signals [you can set the sample size, 2 is the 
minimum], and my P3 never shows the same reading as my S-Meter on CW or 
SSB except when I'm doing RTTY or some other constant amplitude mode, 
and sometimes even those aren't exactly on what I expect them to be.

4.  I don't think it's a problem for you, it's just inherent in the 
technology.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2014 Cal QSO Party 4-5 Oct 2014
- www.cqp.org