Hi,

I did replace the RCA audio cable with a cat-5 double shield cable. But
that cable now runs from the geophone to the amplifer board, but the
first two meters are RCA audio cable, but I don't think that is going to
be a problem. I hope that this is good enough to protect the signal from
electronic noise and other sources of noise (mobile phones (GSM) and
other wireless hardware).

Regards,
J=F3n Fr=EDmann.

On fim, 2010-05-13 at 13:48 +1200, Mark Robinson wrote:
> J=F3n Fr=EDmann wrote:
> > Hi all,
> >=20
> > I did replace my cable the other day from Cat-5 shielded cable to a RCA
> > cable that is also shielded. But with the Cat-5 cable I did not get
> > electronic noise. But with the RCA cable I do. I rather do not want to
> > switch back to the Cat-5 cable, as it is harder to manage.
> >=20
> > What might be the reason why I am seeing electronic noise on the RCA
> > cable ?
>=20
> Hi J=F3n,
>=20
> The type of cable is probably less significant than the way it's connecte=
d.
>=20
> For a pretty much bulletproof connection you probably want to use a twist=
ed=20
> pair, shielded, cable. Microphone cable is probably a good thing to ask f=
or.
>=20
> Then you want to connect the shield to the cases of the geophone and the=20
> electronics, and the twisted pair to the terminals of the geophone and th=
e=20
> input of the electronics.
>=20
> This configuration causes most interference to be deflected by the shield=
 and=20
> most remaining 'common mode' interference to cancel itself out.
>=20
> All the best
> Mark
>=20
>=20
> __________________________________________________________
>=20
> Public Seismic Network Mailing List (PSN-L)
>=20
> To leave this list email PSN-L-REQUEST@.............. with=20
> the body of the message (first line only): unsubscribe
> See http://www.seismicnet.com/maillist.html for more information.

__________________________________________________________

Public Seismic Network Mailing List (PSN-L)