I really don't want to over simplify the process....but...an first IMHO
one should determine how much noise is actually in the shack. A simple
test is to put a 12 battery on the radio and listen to the noise
level(s). then go and cut the main circuit breaker where city power
comes into the house and not just the shack.
If you are not experiencing any noise drop turning your ham shack into a
"clean room" may not be worth the effort or experience. If there are
noise proud devices in the house these can be localized by turn house
breakers on and off while will having the radio on a battery with the RX
antenna. If the AC breaker to the shack makes any increase, it might
be easier to eliminate the device(s) one by one. Wall warts, routes,
lamp voltage controllers, switching supplies, and thermostats etc. can
all be found this way without the expense of a EMF/EMI chamber to
operate out of. Here in the tropics the propagated QRN normally is so
many db's stronger than any device such a simple loop antenna, like the
one that comes with the AM/FM tuners may be worth trying as a sense
antenna. Also a hand held portable AM radio tuned to 1710 noise can
give you some ability to find a null direction inside the house.
A multi-band portable with a high range of 30 Mhz can get you closer to
some noise source such as power line stuff but remember the vertical rod
is the RX antenna past the BC band. Some radios and amateur HT's and
scanners even do AM in the aircraft band starting at 108Mhz. If you
hear noise with the same foot print that you have in the shack, when you
cruise around with the portable, your are probably standing next to the
noise source.
73
Herb Schoenbohm, KV4FZ
On 6/24/2012 5:30 PM, Bruce wrote:
> Regards
> Jose Carlos
> N4IS
>
>
>
>
> Great information Jose. Good to see various ways to achieve an effective DX
> station from your small lot. Your call sign in the 7o6t log book says
> a lot about your station.
>
> It's interesting, and fun to plug in various North American call signs into
> the DX-pedition logs to see who's making it.
>
> 73
> Bruce-K1FZ
>
>
>
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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