Dear Andy, LF Group,
----- Original Message -----
From: Andy <[email protected]>
To: <[email protected]>
Sent: Wednesday, November 17, 2004 2:46 PM
Subject: RE: LF: Loading Coils
> I share my office with some young electronics engineers and was
> surprised that they know very little about RF inductors or Q factor.
> It must be a dying art !
Its not just young electronics engineers who know nothing about inductors.
I
work with a number of middle aged ones (well, 30 - 50 anyway) who also
know
next to nothing about inductors, wire antennas, or even radio
communications.
Actually, there is quite a lot of interest in academic and engineering
circles about inductor Q at the moment - but this is about inductors on
ICs - little planar spirals of several nH that occupy quite a lot of space
on most "system on a chip" ICs containing RF transceivers for "Bluetooth",
"WiFi" and so on. A state-of-the-art Q for one of these is about 5 - 10 ...
even with lousy Q like this, circuit designers find they can't live without
them for amplifiers and oscillators and the like, despite spending half a
century inventing circuits to try and get rid of inductors!
some graduates can't even apply ohms law to a practical
situation.
As someone who occasionally has to help undergraduates do this, I'm afraid I
have to agree. V = I x R they can usually cope with, but I = V/R is a bit
more challenging, involving division as it does ... any mention of kilohms,
microamps etc. and all bets are off!
Cheers, Jim Moritz
73 de M0BMU
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