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Calibration again with V1.2 firm and Nextion


Rene
 

Hello, yes, and no automatic translation so hope this good
After installing Nextion 2.8 and firmware V1.2 CEC almost happy.
I have made an simple kristal ocillator, 12.3550 khz to tune the uBitx.
I don't even know if this is an right methode??
But it seems that the received signal is about 250hz out of line(if this is correct)
I tryed to follow the tips on KD8CEC site but... is there no step to step info for an old guy like me with bad English how to line out the radio??
For me it is onley the feeling that the radio is then perfect when i have my license to start.
Regards
Rene
Netherlands


Evan Hand
 

Rene,

I would still use the three major steps in the video from Ashhar Farhan to align the v6 with stock software and screen.  The steps are the same, the controls are what is different (you swapped out the display, so the keypads will not be the same).

Here is a prior message from me to another person changing out the display for a Nextion:
https://groups.io/g/BITX20/message/81760

Let me know if you have any questions
73
Evan
AC9TU


Rene
 

Okay and thanks for thinking with me, and yes i did that before without the Nextion. So maybe i have to put the old screen back and line out again and after that putting the Nextion and firmware on the uBitx.
But it has to be possible with the ubitx manager....but i have problems to unerstand the whole program cause of my bad English. But thanks again.
Regards,
Rene
Netherlands


Adam Allen
 

I can tell you my procedure to align the v6 Ubitx with Nextion and CEC firmware.  I hook up an antenna and tune to WWV at 10.000mHz on USB. 

Go to the menu and turn Setup to ON.

Go to the Calibrate Frequency setting in the menu. 
It will start at zero and you’ll want to turn the tuning dial until the tone you’re hearing gets lower and lower, and just about goes away. If you tune too far you’ll hear that tone start getting higher and higher again.   The point where it almost goes away is Zero Beat.  

(Note: WWV also plays an audible tone at certain intervals, I can’t recall what they are, so make sure you’re hearing their CARRIER tone and not the audible tone they play at the top of certain minute intervals. A second receiver will help you do this calibrating while avoiding the audible tone they transmit) 

One you have ZERO BEAT, press the Push-to-Talk button on the mic.  

Turn off Ubitx and turn back on.  

Tune to a easy to copy QSO In progress. This is where a second receiver is handy to find one. 


Go back to the menu and turn Setup to ON again. 

Go to BFO CALIBRATE In the menu. 

Adjust the displayed frequency up or down until the voices of those having a QSO sound human. My experience is that it takes adjusting up a lot. I can’t recall off hand what a good frequency starting point is, but I want to say it’s around 11.056?? This is the BFO frequency you’re adjusting, not the actual frequency you’re tuned to on the Ubitx.  


Once the voices sound human press the Push-to-Talk again and turn the Ubitx off and back on   


That should get you really close. You can easily adjust the BFO further if you’re not liking the sound.  But be aware,  if you go to the Frequency Calibrate setting again it ALWAYS goes back to zero. It does not start at what you were previously at, like the BFO does.

 


 

Hi Rene,

A simple crystal oscillator will rarely oscillate at the frequency marked on the crystal.  In order to do that, the circuit would have to provide the exact needed parallel or series capacitance as specified by the crystal maker.  So, usually after making a crystal oscillator, it will need to be calibrated.  Also, a crystal may easily be 250Hz off naturally just depending on the ppm specification of the crystal.  For example many crystals are specified as 20ppm accurate.  That is 20 parts per million.  So:

12.355MHz x 20  =  +/- 247.1Hz

73,  Mark


Don - KM4UDX
 

Rene -- I had the same problems using Nextion and CEC. My English is fine and was no help. My ears bad and hurt me. Hahah. 

The tuning process is the same with the Nextion screen and the CEC software. The screen and software do not change how the radio operates. Adjust tuning with them.  

Here is a other crude simple basic way to get the frequency display to equal the target (correct) received frequency. 

1) put your crystal on a coffee table, or book shelf. Look at it when you want to. But never use it with your uBITX. Hahah.

2) have a way to know your display display error. This process must be simple and accurate for you.

3) use memory manager and change calibration freq by -100, and write it to the uBITX.

4) Restart it. Measure the new error with step #2 above.

5) if the the freq error got smaller then YEA and jump in and down and be very happy. Do #3 again but use -50, or -10 or -5. And do #4 every time. If the freq error got bigger (oh no!) then change calibration by +100, and do the same process using +50, or +10, or + xyz (does "xyz" translate? It means "whatever". Wait, does "whatever" translate?...hahah)

The goal here is to just change the main calibration number using memory Manager and then look at the result. Then repeated the process untill you are happy.

If this seems too complicated, then do what Evan and Allan suggest, or follow AF to the letter. They are really smart folks and their process works. But I had to develop a way that worked for me with Nextion, Memory Manager, CEC. So my process was just to adjust the calibration, observe the impact, and repeat untill I was happy.

My process is like adjusting a telescope. I would twist the focus knob, see the new image, and then keep adjusting untill I got the image I wanted. If I adjusted too far the wrong way, I just turn the knob backward untill happy. Turning the focus knob is like adding +100 or -100 to the main calibreation in MM. Measuring the new ubitx freq error is like looking at the new telescope image and seeing if it is better or worse. And keep adjusting, one way or the other (+ or -) untill happy. 

This worked for me and I could understand it because it is physical (measurement-based).

So just change the main calibration untill the freq error disappears. Done!

Don
Km4udx





2) pick a way, a method, a procedure 


Rene
 

Okay Don, i am gonna try on my day of this week. But thank you. Great, begin to like (finaly) this radio more and more.
Regards,
Rene
Netherlands