[Phys-L] physics in the real world : WAN in a cage2
- John Denker via Phys-l <phys-l@mail.phys-l.org>UnsubscribeTo:Forum for
Physics EducatorsCc:John DenkerSat, Sep 30 at 6:30 AMHi --
Here's a fun example of physics in the real world: What's wrong with
this picture?
Overview:
https://av8n.com/physics/img48/wan-printer-cage.png
Close-up:
https://av8n.com/physics/img48/wan-cage.png
When I saw that setup, I sent an email to the guy in charge, saying:
Fastening the wide-area-network (WAN) base station inside the cage is
clever in terms of convenience, but it's asking for trouble. Physics
says the cage will interfere with radio wave propagation.
- /snip/
A couple of anecdotes come to mind.The Cantenna.
A monopole mounted in a coffee can makes a useful wifi signal boost, at the
cost of making the feed directional - perhaps 30 degrees beam width.
Driverless Transport in a Ford Plant
I was called to an English Ford plant at Daventry which also located a big BBC
MF broadcast transmitter.a few miles away in line of sight.The site was
reporting intermittent glitches in their Digital Equipment control system which
routed the transport drones (quite advanced for the period - 1970s.)I had the
enclosure shielded with chicken wire - still the glitches continued.At length,
the new style disk controller (RK11D) was replaced with the older RK11C and the
intemittent vanished. The disk controller design bug was soon fixed, happily.