Are you sitting in a puddle - of RF?
One thing you can do when suspecting RFI in the shack is to just see how much RF is around. I do this with a sensitive RF meter based on an Arduino, OLED display and a AD8307 log detector module. See this previous blog posting for details.
The circuit is very simple. It is an Arduino Nano with connections
* A4 & A5 (I2C bus) to the OLED screen
* A3 as a DC input from the AD8307 module
* AREF for the A/D converter from a 3V3 voltage regulator
Power is from a 12V input feeding the Nano and the 3V3 regulator. Nano 5V output to AD8307 & OLED display.
The new Arduino sketch code for this project SIMPLE_WATT is here (note you must load the Oled.h header and the U8g2 library for the screen display (download libraries.zip and put them in your Arduino libraries folder). Unplug the 12V supply, connect the Nano to the IDE on your PC and upload the sketch, then plug in the 12V to establish the 3V3 A/D reference.
An extending aerial is connected to the SMA (50R) input connector.
Note: if a 2K2 resistor is placed in series with the input then the meter will read -30dB down, or up to 20W (= 20mW) input across a 50R antenna or dummy load.
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