I haven’t done this for a while, but it is one of those things that should be on your list of things to do periodically around the house, particularly if you are extremely sensitive to radio frequency noise.
“Yeah, yeah…sounds like engineering crap to me…”
Maybe because it is. But it doesn’t make it unimportant.
Granted, if you listen to FM radio and streaming only, chasing down AM radio noise is a time sink. But, with winter coming, there’s a certain magic in being able to tune the dial and mentally transport yourself to a different city.
Up in Seattle, as a young whippersnapper, I listen to Ira Blue on KGO – first of the talk radio greats.
I can categorically state that I sleep better when two conditions are met in my surroundings.
First, I like to sleep grounded. We have been enjoying our “earthing half sheet” for months now and consider it a worthwhile experiment.
Secondly, I don’t do well when there is electrical noise around. For someone who has spent half his life around AM and FM radio stations, that might seem paradoxical.
But there are radio signals (which are not terribly disturbing to my energy) and there are audio signals superimposed on those carriers.
That ain’t noise.
No sir, what I’m talking about is the broadband hash that comes of line-frequency switched mode power supplies. This are simply god-awful things to hear.
The Test Tool
I have a cheap AM/FM radio of the sort you can get for $20-bucks. I keep it next to the bed and when I wake up in the middle of the night (see Brain on Fire) and can’t get back to sleep, I will tune around the AM radio band and unless there is a big geomagnetic disturbance, either Ground Zero or Coast to Coast AM will be coming in from WOAI down in San Antonio.
I haven’t been listening much to the radio lately because I have been so damn busy. Flight plans, travel plans, reservations, cruise, writing, novel, finishing up projects around the house – there’s a daily list that never gets down. You know how that rolls.
But the other morning, I happened to wake up and there went the brain…not on fire yet, but definitely smoldering.
The quickest way to zone out, I figured would be a dose of AM radio. So I turned on the radio and @#$%T^&*BZZZZTTTTT!!! Static.
From one end of the AM dial to the other…static. Horrible whining generator noise broadband power supply noise. I have a pretty good ear for signal strength and in most positions, the noise on the little radio would have been 40 to 60 over S-9 on a real communications receiver…
….except… There was one position where if I held the radio absolutely steady and not letting it move more than an eighth of an inch, the static would be off to the side of the built-in AM ferrite bar antenna (which is very directional) and I could hear the station.
Hell of it was that each time I was about to snooze out, my hand would move, thus the radio and I’d get another earful of @#$%T^&*BZZZZTTTTT!!! Static.
Knowing the only tool I would need would be this AM radio, tuned between stations around 700 on the dial, I swore that before the day was out, I would find the source of this damn electrical PITA and solve it once and for good.
The first thing I did was wander around the house. AM radio on. Seemed like the noise was louder in the bathrooms and the kitchen, but couldn’t be sure.
OK, step two then: I killed all the power to the house.
Whoosh…….just nice normal atmospheric noise. Please.
Next: Turn the big stuff back on:
Stove, hot water heat, dryer. Blissful Whoosh….as quiet radio bands are supposed to sound.
One by one the breakers went on…until finally, next to last breaker on the right side of the panel was flipped on. Care to guess?
@#$%T^&*BZZZZTTTTT!!! Static.
OK…now all I needed to do was wander around the house and find that circuit and begin to manually unplug things.
There, in the kitchen, I found my culprit.
Our Foodsaver!. What the hell?
So I grabbed an AC line filter and threw it on thinking that ought to cure the problem.
Wrong.
Actually made the noise worse.
The simple remedial action was to unplug the Foodsaver. There was something else about this outlet that was interesting: Even plugging in the lame $15 Wal-Mart toaster increased the noise level a bit.
Damn odd, curious, and confounding.
Now I have another project on the list: Dig out my outlet checker and find out what’s going on with that outlet. Is the ground off it? Are the hot and cold wires reversed on the plug? Or, WTF is going on with it?
That’s as far as I got on it…there are more pressing items. But sure as hell, this was a strange one and while I love my Foodsaver, the idea of this outlet being noisy leads to all kinds of other suppositions.
Might a GFI protector be in the process of failing and somehow that’s figuring into how things on this circuit are working? Is the neutral and ground touching?
Or, is the Foodsaver power supply in this particular unit really noisy (electronically) for reasons that aren’t clear to me, except there would have to be a solid-state switch to turn the sealing element on and maybe that somehow is connected to the AC line?
Hell of a fine adventure.
By the way, when you find a problem (like this one) where you can narrow down the source of noise (which went completely away when the Foodsaver was unplugged) you can use the noise source to “calibrate the null” on your AM portable radio.
This is a true story: When I was young I learned that with a cheap AM radio like this, and a $5-compass, that you could steal a boat in any harbor in the world and go anywhere you want with nothing more than an AM radio and some stations that identify themselves often.
By daylight, it’s more useful to follow jet contrails, but you get the idea there, right?
If you’re not tracking yet, go watch this video about how Ira Blue on KGO brought fishermen home through the notorious fogs off the Golden Gate:
Have fun…I sure did, and it was a dandy 15-minute break from not getting the rest of the stuff on my list done on Wednesday.
I have been chasing noise sources this way for more than half a century. Most common culprits are fluorescent light fixtures, silicon-controller rectifier based dimmers (SCRs) and Triacs plus switched mode power supplies.
In the event of a real serious EMP type event, the good news is that the AM radio band should be exceptionally clear of manmade noise like this. The only downside is you may die in the ensuing violence. But the DX’ing (distance listening)_ should be superb.
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