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Raduino synthesizer outputs different for v6 uBitX vs. v4 uBitX boards


lwhfac@...
 

I'm homebrewing a clone of the Raduino control board currently described on the HFSignals webpage. The new v6 version of the uBitX PWB uses an 11.059 MHz crystal filter whereas the older v4 board that I have used the 12 MHz crystals. Wouldn't this require some code modifications in the 2nd LO and BFO Si5351 outputs? Has anyone adapted the newest Raduino for the older revision uBitX boards? Thanks!


Arv Evans
 



might be interesting.

image.png
The block diagram may help to answer your question.  Yes, if using a different
frequency crystal filter you will need to change the CLK-1 and CLK-0 outputs
of the Si5351 to compensate for that change.  You can change the software
to do this by default, or maybe just change the frequency memory during setup.

Reasons for the change could have been to decrease intermod, to change
unwanted harmonic mixing, or to avoid interference from the USB clock.

Arv
_._





On Sat, Feb 27, 2021 at 1:00 PM <lwhfac@...> wrote:
I'm homebrewing a clone of the Raduino control board currently described on the HFSignals webpage. The new v6 version of the uBitX PWB uses an 11.059 MHz crystal filter whereas the older v4 board that I have used the 12 MHz crystals. Wouldn't this require some code modifications in the 2nd LO and BFO Si5351 outputs? Has anyone adapted the newest Raduino for the older revision uBitX boards? Thanks!


lwhfac@...
 

Tnx for the quick reply. That's what I figured. Now I don't even know why I asked the question! Ashar explained something about some spurs due to the original 2nd IF of 12 MHz beating with the uP's clock and that's why he moved the 2nd IF. I built the v4 board some time ago, applied many mods/fixes (15 of them!), and really love the little thing. Now, I see the new touch display (I didn't check on all this until recently) and much better UI, so I figured that I'd just mashup the new controller/display with the older radio's PWB. Since I have all the parts, I'll just hack the code a bit to make things work. Have a great day!
Larry N2AJX


Evan Hand
 

Larry,

The SSB filter is one of the things on the mainboard that limits what the BFO frequency can be.  Just changing the Raduino will not change the SSB filter, so the base v6 code from HFSignals will not work with a 12MHz SSB Filter.  You will need to go in and change a number of the #defines if they are available.

If you have already made the fixes for the spurs and harmonics on the mainboard, then I would suggest looking at the KD8CEC Nextion display and Dr. Ian Lee's software.  It is one of the recommended upgrades on the ubitx.net site.  It has a true graphic display that you can add an S Meter sensor as well as other more extensive mods that allow for things like CW decoding and spectral displays.

The v4 upgrade is relatively easy, as you can pick the screen size that matches the size of the Nextion file that you can find.  There are up to 7" display files that make it really easy on older eyes like mine.

The other thing is that you can do it in steps.  The software has a version that works with the v4 stock 1602 display.  You can get that part working before you invest in the graphics display.  Then upgrade the software for the Nextion display.  It would not hurt to try the software, as you would not need to make any hardware changes.  Here is the link to KD8CEC GitHub page:
https://github.com/phdlee/ubitx/releases/tag/v1.20

Download the zip file and then extract the files.  The directory for the v4 is the uBITXV234.  Read the FileNameInfo.txt file to help show which one to use.  You will need Xloader to install the firmware (also avoids any Arduino IDE settings issues).  You can get that here:
http://www.hobbytronics.co.uk/download/XLoader.zip
or
https://github.com/binaryupdates/xLoader

If you do go with the KD8CEC software, there is a PC program that makes adjustments and settings savings easy.  That is called Memory Manager and is available here:
https://github.com/phdlee/ubitx/releases/tag/v1.11

That code only works with the KD8CEC software, not any of the stock software from HFSignals.  It would have been nice if Ashhar Farhan had included an easy way to read what is currently in the EEPROM settings.  The current program goes back to the default setting if you go in to tweak the calibration.

You might also want to check out the ubitx.net site.  It has a lot of information as well.

73
Evan
AC9TU


Jerry Gaffke
 

The move to an 11.059mhz IF was done to avoid a beat note from the 16mhz processor clock.
     https://groups.io/g/BITX20/message/63636
     https://groups.io/g/BITX20/topic/ubitx_help_strong_audio/8872690

The 12mhz USB clock is not running unless the rig is connected to a host computer.
A few folks were hearing that nasty audio tone even when the USB chip was inactive.

Only some v3,v4 uBitx rigs were affected, as the 16mhz ceramic resonator on the Nano is not very accurate.

Jerry, KE7ER


On Sat, Feb 27, 2021 at 12:47 PM, Arv Evans wrote:
Reasons for the change could have been to decrease intermod, to change
unwanted harmonic mixing, or to avoid interference from the USB clock.
 
Arv
_._