[mythtv-users] OT: USB inductance (or other) problems with external peripherals

[Jay Ashworth]

----- Original Message -----
> From: "marcus hall" <marcus at tuells.org>

> On Mon, Oct 14, 2013 at 11:50:24AM -0400, Jay Ashworth wrote:
> > ----- Original Message -----
> > > From: "Marius Schrecker" <marius.schrecker at lyse.net>
> 
> > > 2. The problem is the crowded conduit. I'm getting inductance
> > > problems
> > > which are causing noise.
> > > I need to split up the cable runs with max one or two cables per
> > > condiut ( a pain in the *** as I'd need to rip the cellar ceiling
> > > apart (again).
> >
> > Not inductance so much as crosstalk, depending on what else is in that
> > pipe. Power cabling is the only think I would expect to actually
> > cause a problem; the jacket thickness should be enough to protect
> > you otherwise.
> 
> Well, the way that crosstalk gets into a wire is through inductance, that
> is, the magnetic field generated on one circuit couples inductively into
> another circuit.

Sure.  But I was replying more to "inductance along the cable rounding 
off the digital signal pulses", distinguished from the sort that's causing
crosstalk.

Though in the case of long cables, it's generally more the capacitance 
that gets you.

Cheers,
-- jra
-- 
Jay R. Ashworth                  Baylink                       jra at baylink.com
Designer                     The Things I Think                       RFC 2100
Ashworth & Associates     http://baylink.pitas.com         2000 Land Rover DII
St Petersburg FL USA               #natog                      +1 727 647 1274