[Elecraft] Tracking down S9+ noise on 40M

[Bob K6UJ]

Dave,

I don't think you will need the AM radio unless you discover it is not in your house.  Here's what I would do:
*  run the K3 on battery power,  have it tuned to 40 meters where you have the noise.  
* Turn off the main breaker to the house.  Go check the K3,  did the noise go away ?  If it did the noise source is in your house.  If it didn't then it is AM radio search time.  (we can 
   go over sleuthing with an AM radio in the neighborhood later if needed, hopefully you won't)
* If it did then turn on each breaker one at a time, checking each time at the K3.  The noise will reappear when the circuit breaker is turned on having the noise generator.
* Check them all, it could be on more than one circuit.
* Then leave the offending circuit on and go around and unplug, one at a time all the devices on the circuit, checking each time with the K3.  It will go away when the offender is 
   unplugged.  You need to actually unplug each device not just turn them off,  (my DirecTV receiver was a noise generator even when it was turned off the power supply was 
   generating noise.)  

Hopefully it is in your house where you can remedy it easily.  I do this every once in a while myself.  My last check discovered one of the kids external hard drives was a nasty 
noise generator.  Another time one of the battery chargers to my Makita cordless drill was a culprit.  If you have any touch control lamps, I can almost guarantee they are nasty.

good luck and let us know how you do.

73,
Bob
K6UJ


 
On Jan 18, 2012, at 7:41 PM, David Dietrich wrote:

> Hi All,
> 
> Could someone please explain the proper way to track down RF noise in and around my house?  More often than not, I always have S9+ noise on 40 Meters, making anything but really strong signals (S9+) audible above the noise.  I have only had a few instances where the noise was below S9 on 40.  I know I have to power down the house and then bring it up one circuit at a time with my radio on battery power.  I also know I am supposed to use a handheld AM radio to listen as I walk around the house.  I don't know what I should be listening for, or where to tune on AM to hear what I am supposed to hear.  Now that I am getting back into operating more regularly, I would really like to see where some of this noise is coming from; and reduce or eliminate it if at all possible even if it means shutting something off while I am on the air.
> 
> 73,
> 
> David, KC9EHQ
> K1-4 s/n 2051
> K2/10 s/n 7164
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