Adc rx clipping

[Jo Oak]

Hi All

Found a strange issue, when use 12v battery. 3s lipo for my case. The adc 100 is sometimes off and sometimes flashing. Wiki says adc clipping. Why only happened for battery, 12v power supply is ok. Voltage too low? Use 4s lipo?

Eric

[Steve Haynal]

Hi Eric,

3S LIPO is okay for receive. I use 3S LIFE (under 10V) for receive. A voltage of 11V or more is only needed for TX.

I do not see the issue you are reporting. Is there a charger connected to the batteries while you are operating? Those use switching circuits and can introduce noise. Are the cables to you batteries longer than you 12V power supply? Depending on your antenna, the power leads can become part of the antenna and pick up noise. In which part of the spectrum do you see the noise? You can use bandscope in Quisk, SparkSDR and other software to see the entire HF spectrum. You should be able to see a noise difference between with and without batteries. Are there filter or band differences when you run with battery? Most noise comes from 1.8MHz and below. The N2ADR board usually inserts a HPF to block this noise, but if you operate on 160M or do not have your filters configured correctly, then you will see more noise.

73,

Steve

kf7o