Hi Jon,

I am using a shielded microphone cable.

Cat-5e should work better with the higher twist-per-inch and I may try that=
.

Could it still be the sensor pickup coil is really acting as the antenna fo=
r
this type of EMF?

Richard


2011/1/5 J=F3n Fr=EDmann 

> Hi,
>
> You have to use shield cable and ground it properly. That is the only
> way to prvent this type of noise. I use cat-5e cable with shield to do
> this.
>
> Regards,
> J=F3n Fr=EDmann.
>
> On mi=F0, 2011-01-05 at 15:11 -0800, Richard Schneider wrote:
> > Situation:  High amplitude spikes when starting and again on shutdown
> > of engine from automobile.
> >
> >  Sensor is about 3 feet from car.
> >
> > EMF appears to come from auto alternator since I can see it upon
> > engine shutdown.
> >
> > Any suggestions would be appreciated to mitigate the EMF from the
> > sensor pickup coil without relocating it.
> >
> >  How about a lead shield?  The kind the dentist uses for X-ray's.
> >
> >
>
>
> __________________________________________________________
>
> Public Seismic Network Mailing List (PSNLIST)
>
> To leave this list email PSNLIST-REQUEST@.............. with
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>

Hi Jon,
I am using a shielded microphone cable.
Cat-5e should work better with the higher twist-per-inch and I may try t=
hat.
Could it still be the sensor pickup coil is really acting as the antenna=
 for this type of EMF?
Richard


2011/1/5 J=F3n Fr=EDmann <<=
a href=3D"mailto:jonfr@.........">jonfr@.........>

Hi,

You have to use shiel=
d cable and ground it properly. That is the only
way to prvent this type=
 of noise. I use cat-5e cable with shield to do

this.

Regards,
J=F3n Fr=EDmann.




On mi=F0, 2011-01-05 at 15:11 -0800, Richard Schneide=
r wrote:
> Situation: =A0High amplitude spikes when starting and agai=
n on shutdown
> of engine from automobile.
>
> =A0Sensor =
is about 3 feet from car.

>
> EMF appears to come from auto alternator since I can see it up=
on
> engine shutdown.
>
> Any suggestions would be apprec=
iated to mitigate the EMF from the
> sensor pickup coil without reloc=
ating it.

>
> =A0How about a lead shield? =A0The kind the dentist uses for X=
-ray's.
>
>


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st (PSNLIST)


To leave this list email PSNLIST-REQUEST@.............. with
the body of the message (fir=
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See http://www.seismicnet.com/maillist.html fo=
r more information.