Re: Are MilliHenries obselete?


"Spehro Pefhany" <speffSNIP@xxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:bgh392duv6lc2f12shmfhbk8a9khm3mk28@xxxxxxxxxx
On 15 Jun 2006 13:06:26 -0700, the renowned "Tom Bruhns"
<k7itm@xxxxxxx> wrote:


martin griffith wrote:
Just been trying to find some *inexpensive* 8.2mH inductors for a
20K-ish bandpass chebyshev filter, Digikey(UK), Farnell, RS
components, nothing that I could find.
I suspect that these have become very 'low volume' items. A gyrator can be
done with an op-amp, or one transistor, and in terms of production costs,
is so much cheaper, and can actually often perform better, leading to the
inductor, tending to die.
I'd suspect it'd be easier to use the gyrator for this, than wait for the
inductor...

Best Wishes



.

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