In a message dated 1/26/2007 7:13:29 AM Eastern Standard Time, magoo@isp.ca
writes:
Wonder if some of those noises others have been describing from time to time
are caused by either MV or sodium lights starting to go bad.
Bill, VE3CSK
Here in my NOISY suburban QTH MOST of the local noise trouble is lighting.
If not the sensor contacts on street lights then residential auto-on lighting.
I have also found a major issue comes from low voltage lawn lighting - the
bulbs (and this applies to indoor under cabinet type LV lamps too). These
bulbs run very hot and have a propensity for the element to open
intermittently. That forms a little spark gap which is always good for
challenging topband
local noise. It is very difficult to determine which bulb is the offender
because the lamp works under those conditions but it a bit dimmer than the
others IF you look very carefully. If you tap gently on the small glass
envelope
it will often cure the noise completely because the intermittent filament
welds itself back to a more constant state OR it will open completely and the
light will go out. But LV systems in general have gotten much worse
regardless of bulb issues because many employ "matchbook" transformers - tiny
switching power supplies which mount in the fixture itself. Here I rewired
the whole
kitchen (directly over the shack) into a 20A Astron clean DC supply because
the LV AC lighting systems killed me on 160.
Pete W2PM
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