S-Meter tracking

Below are my measurements of my IC-7610 S-Meter. The first graph is in S-Values up to S9 and displays the poor performance of the meter. Quite disappointing considering this is an SDR (Software Defined Radio). I expected better from this class of radio. Another grudge, why is the meter reading differently by engaging the PreAMP. This is a Radio that is defined by software SDR !

There is NO NEED to change and to track so poorly! Let's hope a a future firmware upgrade improves on this!

The second graph is in dBm up to -13 dBm (S9 +60). We can see clearly that the radio tracks from S9 to S9+60 without a preamp on 40 m correctly (maybe ICOM's engineers are only interested in signals above -73 dBm).

It is interesting to see though, that the default Attenuator (ATT) values are in 6 dB (6/12/18 dB) per step, which would indicate that ICOM knows about the 6 dB scaling for S-Values.

UPDATE: From ICOM S-Meter blurb for the IC-R8600!

Absolute Value of RSSI (Received Signal Strength Indicator)

The IC-R8600 shows S-meter, dBμ, dBμ (emf) and dBm meter types in the RSSI. The dBμ, dBμ (emf) and dBm meter has a high ±3dB accuracy* (between 0.5–1100MHz) that can be used for measuring signal strength level.

My ANAN is tracking spot on, a K3 that I had was very good and did not change values regardless of preamp or att. A Yaesu FTdx 5000 that I owned had a very linear S-Meter but not quite up to the standard. I would have thought that, since the ICOM is not picking the S-Meter of the AGC anymore, that ICOM would make sure that a few lines in the firmware (SDR = Software Defined Radio) would make the S-Meter track a lot better than this.