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Old September 16th 14, 02:41 AM posted to rec.radio.amateur.antenna
Lostgallifreyan Lostgallifreyan is offline
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First recorded activity by RadioBanter: Sep 2006
Posts: 613
Default Metal kite reel for portable longwire...

wrote in news:a44e119a-e3c4-4380-b611-
:

Being as the caps used are generally old broadcast variables and such,
you could just have a plastic cover over it. But I use all mine indoors
where I can turn them, and don't worry about that. I'm not going to sit
out in the rain to listen to a radio. :/


I've been caught up in other doings for a while (old Psion machines, buying,
programming, etc..) so I re-marked as unread because I need to read more
carefully, but just a couple of things for this post..

I won't sit in the rain either. I used to repair stuff for people, and
found that dust and airborne volatiles have a habit of settling on air-spaced
cap vanes, and some old tuning caps get very furry with surface corrosion
too, making them harder to clean safely. Even a dry night can have a heavy
dew... And a few encounters with boxes with IP ratings says those that keep
water out are the ones that are usually best at keeping all the other crap
out too.

The other thing, a question.. Is it important to space the coils out on the
UPVC frame? I imagine that changes inductance, and may be used as a way to
adjust tuning in addition to using a variable capacitor, but is there some
other reason, i.e. is there some specific compromise that aims to get the
lenth of wire into a small spatial region without compacting the coils so
close togeher as to raise inductance a lot? (I ask because I'm considering
possible implications on aiming for a compact portable device. If I can lay
the coil very flat, I'd like to do so.)