Re: IF shift needed for listening correctly V4 UBITX #bitx20help

Evan Hand

There are two possibilities:
1 - You loaded the wrong version of the KD8CEC software.  There is a version for the v5 and v6 ubitx (uBITXV5), and one for v2/v3/v4 (you want this one-uBITXV234).  This is due to the different SSB filter frequencies used in the later versions.
2 - The other possibility is that the ubitx needs to be calibrated. 

By chance did you change the Nano to keep the original if needed to be restored?  The calibration data is specific to a ubitx mainboard/Raduino combination and stored in the EEPROM area of the Nano.  This area is not part of the "Sketch" or program part of the firmware that is downloaded.  It is kept in the Nano.  What this means is that any time that you change the Nano, you will need to recalibrate both the BFO and the frequency (called Calibration).

If you understand the differences, you can use the v6 calibration process.  Otherwise, the steps in general are:
1 - Tune in the BFO using the BFO Tuning aid, or an audio spectrum analyzer program to center the noise of a clear frequency between 300 and 3,000 Hz.  Press the PTT when done.
2 - Use a known AM station (WWV on 5 or 10 MHz is best) to "zero beat" the station's AM carrier.  This is done by first setting the dial to read the frequency of the station, then going into calibration mode, and adjusting for the zero beat.  The final step is to press the PTT, wait 15 seconds, and then reboot.  
3 - go back and redo the BFO adjustment.

Here is Ashhar Farhan's BFO tuning for the v6:
And the BFO Tuning Aid:

Note that the steps to get to the settings is the only real difference with the v4 vs the v6.  You will need to go into the "Yellow Box" mode (press in the encoder) of the CEC software to get to the calibration and BFO setting screens.  Once done, there is a Memory Manager program from KD8CEC that can be connected via the USB port and used to save all of the configuration data if you later need to reload software on the Nano.

GitHub link to the KD8CEC v1.2 firmware: 
You want to use the uBITXV234 folder.

I hope this helps with your calibration issue.

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