It seems that my issues is the same one discussed at the thread you pointed out.
I happeningly ordered some extra Arduino Nano for my another projects, so let me try to switch Nano at first.
What do you think How many of Nano I can buy to get the right one?
I’m just asking you the possibility. No commitment, of course.
// hiro, JJ1FXF
Here's an old thread about audio tones in the receiver,
possibly due to beat notes between harmonics of the 12mhz bfo and the 16mhz Nano processor clock.
? ? /g/BITX20/message/54576
Easiest solution if you have a v4 uBitx with the socketed Nano:? replace the Nano
Jerry
On Sun, Aug 12, 2018 at 07:58 PM, JJ1FXF wrote:
Though it took a little longer time, finally my uBitX seems to be working very well now, for which thank you for advices here so far.
Then, another question to ask you who experienced the same issue.
I hear high frequency noise behind the band noise that my iPhone freq meter says it’s about 2,700Hz. (I’m not sure if this app is reliable or not)
My uBitX is not in a metal case, yet. And I use a small powered speaker.
Maybe it comes from Raduino or main board of uBitX, or possibly the 12v power supply.
Since I’m planning to bring my uBitX to a local lab in order to measure its spurious emission this coming Wed, I’d like not to mod much things on hardware coz it may possibly bring another trouble to me.
I just hope that some capacitor in the line of speaker or some small mod can solve this issue at this moment.
Looking forward to your advice.
Thanks!
HIRO, JJ1FXF