The Inv L FCP continues to perform.
After a nice long hot summer here which is unusal here I was on last
night around 0230 and worked K6ND, WJ3A, G4EIM. LY2OU, UY0ZG.
While operating I started hearing at regular intervals somewhere of in
the distance "beep beep" pause "beep beep" ...upon investigation I
found the kitchen oven had turned itself on and was awaiting further
instructions from the keypad. I was running about 600w and the flat-top
of the L runs more or less over the kitchen area.
I reread the RFI article re kitchen ovens in May 2012 QST and my first
reaction was to try and place by-pass caps as described in the artcile.
Howevere I thought I would try the simplest thing first. This morning I
was able to place two snap on chokes of #43 material over the 240V wire
inside the access panel at the back of the stove. The 1/2inch hole in
the cores is not big enough to snap over the cable as it enters the
stove. So I removed the plug from the wall and removed the access panel
of the stove. There was enough room in the area to accommodate two snap
on chokes -- i ran two wires through one core and one through
another. There was just enough space to accomodate the cores.
Upon testing at 600-700W the oven appears to be unaffected now.
hopefully it remains thus.
The old inv L and on the ground non-uniform and erratic radial system
did not cause this issue so do I conclude that the effective radiated
field from the FCP Inv l is that much stronger? Yesterday I also did
some more work on the FCP ...when I initially built it I used 1/2inch
pressure treated wooden spacers and tie wraps. Yesterday I replaced the
those spacers with 1/2inch "PEX" (HDPE material) water pipe painted
black. These spacers appeared to cause a slight shift in the SWR curve
for the L...raising somewhat away from 1800khz. I am wondering about
this material and whether its the right stuff to use?
By the way the oven model Jenn-Air JES8850ACB ( same number for Maytag)
73 Frank VO1HP
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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