The type of lamp cord common in South Africa (don't know about other
countries): Two conductors of 0.75mm^2 cross sectional area insulated with
about 1mm of white pvc and a spacing of around 2.5mm has an impedance of
aproximately 60 Ohms. Close enough to 50 to use for quick&dirty dipoles
without balun or tuner. Though have no idea of the velocity factor and
don't
really need to bother as I just pull apart the cord until I have what
looks
like enough to get a good swr. Then fine tune by pulling more or cutting.
A
swr of about 1.3 is achievable.
73
Roger ZR3RC
I've heard that lamp cord was low-impedence but had forgotten what the
impedence was.
Do you just use some tape once you unzip the length you need - to keep it
from self-zipping from the tension?
I also heard it had a pretty high loss - But like you say - for a quick-and
dirty antenna and feedline, its a good trick for a ham's bag.
Thanks for the info.
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