[FEATURE]6m S Units definition (option) about thetis HOT 7 CLOSED

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@VK6CPU have you tested this? Because it is already coded for. 30MHz and above is using the -93dBm level for S9.

For example, a signal rx'ed on 50.075MHz gave the following with the legacy meters

S meter : S9 +20
dBm : -73.7 dBm
uV : 46.36 uV

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The S-meter standard reference levels are defined by IARU Region 1 Technical Recommendation R.1, as ratified at both the Brighton 1981 and Torrelmolinos 1990 meetings. This standardization is documented in that recommendation as follows:

STANDARDISATION OF S-METER READINGS

1. One S-unit corresponds to a signal level difference of 6 dB,
2. On the bands below 30 MHz a meter deviation of S-9 corresponds to an available power of -73 dBm from a continuous wave signal generator connected to the receiver input terminals,
3. On the bands above 144 MHz this available power shall be -93 dBm,
4. The metering system shall be based on quasi-peak detection with an attack time of 10 msec ± 2 msec and a decay time constant of at least 500 msec.

Unfortunately, this leaves S-meter reference levels undefined for the 6M band. For 6M, Thetis currently uses the "VHF" reference level of S9 = -93dBm. Whether this is correct or not is hard to say given that the IARU never defined it.

73,

Scott

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@ramdor - yes. Above 29.999999 Mhz the transform flips from the -73 to the -93 dbm reference.

As an enhancement, on my part its fairly low priority.

As Scott says 6m (and 8m) dont appear to be covered by the IARU definition - but the HF definition seems to be the one adopted/implemented by most rig manufacturers. Having checked with several other Ops Flex, Yaesu, Icom all use the IARU HF defintion for 6m.

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added feature. Note: Cat SM command will need to be modified to align with this. ToDo

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