Many laptops now-a-days have mini-pci wifi internal wifi cards for
wireless internet. Laptops such as the IBM Thinkpad series apparently have
an antenna built into the top of the display, which enhances wifi signal.

Does anyone have any idea what type of antenna is used? A neighbor has
a wifi coverage problem and he says he measures a (DC) short circuit at the
little coax coming from this built in antenna. I suspect this might be
normal, but would like further opinion here. Thanks.

I believe that some of them use an inverted-F configuration or
straight-F configuration, either printed right on the PC board or
mounted above it. My recollection (and brief Googling on the net)
suggest that such antennas use a shorted inductive stub as part of
their matching/tuning arrangement, and will thus look like a short
circuit at DC.

--
Dave Platt AE6EO
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