Bill/Bob, ZZSM is not working for me yet... :-(
For example: When I read ZZSM0 through the serial port with a PowerSDR S-Meter reading of ~1, I get ZZSM0106. The S-Meter on PowerSDR reads -119 dBm. If I use the formula 'dBm = (ZZSM/2)-140' I get (106/2)-140 which equates to -87 dBm. That is a difference of 32 dBm. Any suggestions are appreciated... Dave (W4DJW) -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Bill K7UOP Sent: Wednesday, February 02, 2011 5:42 PM To: 'Bob Tracy'; 'FlexEdge' Subject: Re: [FlexEdge] CAT S-Meter readings Thanks Bob, good info. I take it DttSP is a class internal to PowerSDR. The main thing I get is the scaling: sm = ((int)num+140)*2; So for me, num = sm/2-140 (for num in dBm). Ahh yes, the output of my program now looks better. Thanks, Bill - K7UOP -----Original Message----- From: Bob Tracy [mailto:[email protected]] Sent: Wednesday, February 02, 2011 3:10 PM To: 'Bill K7UOP'; 'FlexEdge' Subject: RE: [FlexEdge] CAT S-Meter readings Bill, The way it is calculated depends on the radio model, here's the code from ZZSM: We first get the raw signal strength from DttSP num = DttSP.CalculateRXMeter(0, 0, DttSP.MeterType.SIGNAL_STRENGTH); Then we plug in the calibration offsets (this is where it varies by radio model, F5K code shown) num = num + console.MultiMeterCalOffset + Display.RX1PreampOffset + console.RX1FilterSizeCalOffset + console.RX1PathOffset + console.RX1XVTRGainOffset; if (console.RX1Loop) num = num + console.LoopGain; Finally, we scale the results and return a fixed length string num = Math.Max(-140, num); num = Math.Min(-10, num); sm = ((int)num+140)*2; return sm.ToString().PadLeft(3,'0'); Hope this helps, BobT, K5KDN -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Bill K7UOP Sent: Wednesday, February 02, 2011 3:38 PM To: FlexEdge Subject: [FlexEdge] CAT S-Meter readings The CAT Command Dictionary says: ZZSM P1 P2 P2 P2; P2 = 000 to 260 Each increment of ZZSM is approximately 0.5 dBm. To get to actual dBm I've tried dBm = P2 / 2 - 130 but it doesn't quite jive with what I'm seeing on the Flex 5k s-meter. Is there an offset? What is the conversion from P2 to dBm? de Bill - K7UOP _______________________________________________ Flexedge mailing list [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is used for posting topics related to SDR software development and experimentalist who are using beta versions of the software. _______________________________________________ Flexedge mailing list [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is used for posting topics related to SDR software development and experimentalist who are using beta versions of the software. _______________________________________________ Flexedge mailing list [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is used for posting topics related to SDR software innovation and other technical SDR topics.
