I recommend a pi-network RC filter of two 220uF capacitors to ground and a 10 ohm resistor with the V+ from your power supply on one end and the Raduino V+ to the LM7805. Peter VK3YE details that fix in this video. Jim W0EB 47-ohm 2W resistor? on the Raduino V+ line doesn't hurt either. I've installed it in my Bitx40 and now hear very little noise including LCD update "clicks".
https://youtu.be/zOGzQDwFOag?t=2m53s
The major clicks from the tuning pot can be cured partly with shorter leads and the included capacitor between wiper and ground. The clicks are from the data signals to change the LCD. Allards PE1NWL software (with a 10k ohm resistor) can "lock" on frequency on transmit if the issue doesn't go away after mounting it all in a case.
https://github.com/amunters/bitx40/blob/master/operating-instructions.md
I second the 1k ohm resistor on the wiper of the volume pot. It limits oscillation of the LM386 near full volume.
For the most part, your video shows my experience with the Bitx40 as far as normal noises to be expected as provided from hfsignals. I happen to live in a cinder block RF cage, so an outside antenna is a must.
Finally, I've noticed if I use the given 6-7 inch (150mm-175mm) headers to the antenna the loss seems quite high and the radio seems deaf at first. The original instructions state clip the antenna leads to less than 2 inches (50mm) but in my experience 0.5 inch (12.7mm), strip and connect to coax and/or the BNC connector.
To summarize, I made the mods in this order:
1) 1000 ohm resistor on volume wiper
2) shortened all leads
3) RF Gain potentiometer
4) W0EB Raduino 47 ohm resistor
5) VK3YE DDS VFO noise filter
I recommend you install them in this order based on effectiveness:
1) shortened all leads
2) VK3YE Noise filter
3) W0EB Raduino 47 ohm resistor
4) 1000 ohm resistor on volume wiper
5) RF Gain poteniometer
I hope this helps, Heinz
73 de Jacob AG7CT
PS. I'll try to get a video made to demonstrate, but it will be a bit before I can set up everything to do it.
PPS. I highly recommend the W0EB 47-ohm on the Raduino of the uBitx as well. Does as decent job dropping the noise level of the uBitx.
