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Power instead of S-Meter for CEC-software? #ubitx #arduino #smeter

anders@...
 

Hi all,
I guess it would be possible to measure power output instead of signal strength in the CEC-software, and display in the S-meter. I have copied the Elecraft K2:s RF-detector which gives me between 1 and 4V (~1-10W) that I would like to feed to arduino pin A7. What changes has to be done in the firmware to make this work? Anyone?

Evan Hand
 

The answer will depend on what other options you have implemented or plan for the CEC run device.  If you are not using or plan to use the stand alone signal analyzer with a second nano, then it should be just a mater of configuring the CEC software as if it were the analog S meter interface.  I have not done this, so would assume that you can adjust the calibration of the display via the configuration or memory manager software from KD8CEC. 

If you plan to use the stand along analyzer, then it would be a little more involved.  I do not have an answer for that at this time.

Please verify the above before making plans or changes, as I am going from memory and have not looked at this for a long period (for me) of time.

73
Evan
AC9TU

Jack, W8TEE
 

Check out the map() function. It allows you to map the 1-4V read on the pin to a range of values. The voltage readings are returned as values between 0-1023. You can then map those values to whatever you need.

Jack, W8TEE

On Tuesday, February 19, 2019, 11:47:11 AM EST, anders@... <anders@...> wrote:


Hi all,
I guess it would be possible to measure power output instead of signal strength in the CEC-software, and display in the S-meter. I have copied the Elecraft K2:s RF-detector which gives me between 1 and 4V (~1-10W) that I would like to feed to arduino pin A7. What changes has to be done in the firmware to make this work? Anyone?

KE2GKB
 

On top of this you can do it right inside of the CEC firmware's Configuration software "uBITX_Manager'. You would just set it to Follow the expected Power level for each S-Meter level, Some playing with it may be required however due to how it "Labels things".
--
Tim Keller - KE2GKB
https://shop.kit-projects.com

anders@...
 


Thanks for input! The principles are now clear to me. I will try it out, first I will check if the so called "S-meter" on the display is available in transmit mode (anyone knows?), and then if the RF-detector produces enough current to be measured by Arduino, or if I have to apply some circuit involving LM358 or alike.

73's

Anders SM0HPL

SUNIL A R
 

Tu 73...

alphamale@...
 

The code for the second nano S meter has referen e to pins used for power measurement. Is KD8CEC working on something here already?

I'd be interested in seeing your circuit and trying this myself.

Ian Lee
 

It's not yet implemented.
I am working on uBITX V5 firmware now. I will test this by creating the simplest sensor to complete this task and measure power.
A little preparation work has been done on Second nano's (stand alone S-Meter) firmware for power measurement.

Ian KD8CEC


2019년 2월 20일 (수) 오후 11:40, <alphamale@...>님이 작성:

The code for the second nano S meter has referen e to pins used for power measurement. Is KD8CEC working on something here already?

I'd be interested in seeing your circuit and trying this myself.


--
Best 73
KD8CEC / Ph.D ian lee
kd8cec@...
www.hamskey.com (my blog)

anders@...
 

The circuit I tried is the simplest possible. A voltage divider 1.5K/220R followed by a 1N5711 and decoupled by 0.001u, (almost) identical as on the K2 (see schematic, p. 146 https://ftp.elecraft.com/K2/Manuals%20Downloads/E740001_K2%20Owner's%20Manual%20Rev%20I.pdf ). I will see if I pursue this. Maybe my uBITX is officially "finished" without this feature after all ;)

Good luck!

Anders SM0HPL

Mike Short
 

They are never finished. Always something else to try!
Mike
AI4NS