Step 1. Isolate if source is in my house.
I set a battery powered SW radio to AM mode and tuned it to a frequency in the 80m band where the noise was particularly undeniable. Then I went to the breaker panel in the house and turning off the MAIN circuit breaker.
No luck, The noise level at 3630MHz was at Signal Strength 5 with or without power in the house.
Step 2. What Next?
Directional antenna? and What band?
These are not independent. A directional antenna can be used but only on VHF, and VHF also requires the noise source to be close by. For example a 440MHz Beam and a 440MHz hand held AM mode would do the trick. Examples are captured below I will have to decide if I need to go this route.
Cushcraft A4496S 6 Element 440MHz Amateur Radio Antenna
The Cushcraft A449 6S is an effective, economical choice for your 70 cm FM/Packet needs. Great for vertical or horizontal polarization configurations. Mast shown is not included.
- * 3dB Beamwidth, Degrees E-Plane 60
- * Boom Lenght ft.(m) 2.9(0.89)
- * Forward Gain, dBi 10.5
- * Frequency, MHz 440-450
- * Front to Back Ratio, dB 18
Yaesu VX-7R Tri Band Handheld Amateur Radio Transceiver is a triple band (6M, 2M & 440 MHz) HT with extensive receive coverage, and leading-edge features. Power output on 6 meters, 2 meters and 440 MHz is 5/2.5/1/0.5 Watts. It receives the AM and FM broadcast bands, shortwave (AM), VHF and UHF TV audio, VHF Air and public service frequencies.
- * Receiver coverage 500 KHz to 999 MHz (Cell Blocked)
I decided to give the radio in the truck a try. I tuned the AM radio to 1700kHz, the very top of the AM broadcast band. Then proceeded to take a drive around the neighborhood.
My drive route took me past several locations where I thought I may find my noise source; street light standards, the well lighted neighborhood grocery parking lot, several hydro electricity transformers, (the neighborhood has under ground electrical distribution).
What I found was very odd.
There were a few highly localized hot spots quite far from my house.
One was on a housed street about 500m from home, the noise source had the typical 120Hz sounding signature but the source was very localized, as it only presented it self over a <20m class="blsp-spelling-corrected" id="SPELLING_ERROR_11">noise was remarkable strong was; (in descending order)
- In my next door neighbor's driveway
- In my own garage
- In my other next door neighbor's driveway