Thanks for reminding Dragan!
I have updated the instructions at and included the following note:
? Extra Note: If the max. drive level of 8mA is still insufficient for USB mode, removal of C91 and C92 may help.
? These caps cause too much attenuation of the VFO signal at higher frequencies. They're only needed for the analog VFO
? and can safely be removed if you use the Raduino instead of the analog VFO.
73 Allard PE1NWL