[RFI] Receiver settings for hearing RFI?

[Paul Christensen]

> I plan on evaluating my house for HF noise sources by powering the radio
> from a battery and powering down the rest of the house.  I just have to 
> have
> some sources with cell phone chargers, computer routers, laptop chargers 
> and
> such.  Then I'll power up one breaker at a time.

That's a ritual I go through once a month.  It goes much faster if you can 
see the entire band on a panadapter.  Since the display is RF-sampled, noise 
is identified regardless of receive mode.  I use an SDR-IQ receiver, 
notebook PC, and tunable loop antenna.  The netbook's battery is the power 
source for the SDR-IQ and active loop antenna.

Without that kind of setup, sharp impulse noise is probably best detected by 
ear when using wideband AM mode.  The junk usually emitted within the home 
from switch-mode sources generally repeats itself every 30kHz-100 kHz, 
depending on the appliance's switching frequency.  Once you've identified 
the hallmark signature of one switching source, it becomes easier to find 
others.

Paul, W9AC