=0A=0A=0A=0A=0A________________________________=0AFrom: Geoffrey=0ATo: psn-l@...................... Tue, May 18, 2010 10:35:45 A= M=0ASubject: Re: Electronic noise=0A=0AI was assuming electrical noise of a= ny type.=0AJust about any KIND of noise can be handled=0Ain a similar fashi= on by tying eveything=0Atogether to be ISO-Whatever.=0AIf two of the same k= ind and value of resistors=0Aare changed in temp identically then the chage= =0Ashould be somewhat invisible.=0A=0ALike if EVERYTHING is 3C how would yo= u even=0Atell it is 3C except that there is a mystry pressure=0Acausing an = invisible accelerational pressure force if the gas into=0Aa great nothing n= othing. In another 16 billion years it might=0Abe only 1.5c but that pressu= re will still be there if=0Athere is any temperature however slight.=0A=0AI= f any of that makes any sense to anyone.=0A=0ALike hey man like, PV=3DnRT o= r something like that ??=0A=0A=0A----- Original Message ----- =0AFrom: "GPa= yton" =0ATo: =0ASent: Friday, = May 14, 2010 10:10 AM=0ASubject: Re: Electronic noise=0A=0A=0A> Good inform= ation and suggestions.=A0 However, I don't believe that Jon=0A> mentioned t= he SOURCE of his interference or the DISTANCE of his needed run.=0A> Both a= re important factors to consider.=0A> Regards,=0A> Jerry=0A>=0A>=A0 ----- O= riginal Message ----- =0A>=A0 From: Geoffrey=0A>=A0 To: psn-l@.............. m=0A>=A0 Sent: Friday, May 14, 2010 12:02 PM=0A>=A0 Subject: Re: Electronic= noise=0A>=0A>=0A>=A0 At the local hardware store ACE BEST or whatever=0A>= =A0 I found a signal cable suitable for underground buriel=0A>=A0 which has= some kind of grease impregnated beween the shield=0A>=A0 and the cable jac= ket to keep moisure out.=0A>=A0 I installed a 40 foot run of it several yea= rs ago=0A>=A0 and it still seems good. The shield is heavy copper foil=0A>= =A0 which makes the cable not as flexable as it might be with=0A>=A0 a brai= ded shield. You just need to shield the jacket from sunlight=0A>=A0 everywh= ere it might be above ground.=0A>=0A>=A0 Also you should avoid what is call= ed ground loops=0A>=A0 which can indice unwanted noise inside the cable=0A>= =A0 this can be avoided by choosing your gound=0A>=A0 and making sure the s= hield is broken at one side of the connection=0A>=A0 or another to eliminat= e a DC path. I will typically=0A>=A0 break the shield on the side opposite = of the=0A>=A0 side chosen as the primary ground.=0A>=0A>=A0 DC/LOW FREQUENC= IES will travel deep within a conductor.=0A>=A0 But like over 1 MHZ the cur= rent exhibits a skin effect=0A>=A0 and only travels like within the first 1= /8 inch of the surface=0A>=A0 with that skin getting smaller/thinner as the= frequency increases.=0A>=0A>=A0 I shoiuld imagine the impedance is also re= lated to this skin effect.=0A>=0A>=A0 It seems to play a role in antenna de= sign visible as gamma matching.=0A>=0A>=A0 Coaxial cable would be quite sui= table for low frequencies=0A>=A0 if 100% shielded and have a proper BALUNS = to keep=0A>=A0 RF out of the inside of the cable.=0A>=A0 A BALUNS may be as= simple as a series of=0A>=A0 FERRITE beads at=A0 the open ends of the shie= ld.=0A>=A0 The broader the frequency block the more=0A>=A0 beads you need a= nd they are not cheap.=0A>=A0 They come in sizes for one wire or a whole 1/= 4 inch cable=0A>=A0 as a split bead. I have seen them at Radsio Shack=0A>= =A0 in the past.=0A>=A0 You want to make sure what flows on the outside of = a coax=0A>=A0 does not leak into the inside. And, Vice Versa.=0A>=0A>=0A>= =A0 ----- Original Message ----- =0A>=A0 From: "GPayton" =0A>=A0 To: =0A>=A0 Sent: Wednesday, May 12, 201= 0 5:16 PM=0A>=A0 Subject: Re: Electronic noise=0A>=0A>=0A>=A0 > Jon, in the= past I have observed that RCA type (audio) cable may not=0A> have=0A>=A0 >= complete shielding; some ever have had a small thread of wires and=0A> cal= led it=0A>=A0 > shielded.=0A>=A0 >=0A>=A0 > You might try coaxial cable.=0A= >=A0 >=0A>=A0 > Regards,=0A>=A0 > Jerry=0A>=A0 >=0A>=A0 >=A0 ----- Original= Message ----- =0A>=A0 >=A0 From: J=F3n Fr=EDmann=0A>=A0 >=A0 To: PSN-Postl= ist=0A>=A0 >=A0 Sent: Wednesday, May 12, 2010 7:09 PM=0A>=A0 >=A0 Subject: = Electronic noise=0A>=A0 >=0A>=A0 >=0A>=A0 >=A0 Hi all,=0A>=A0 >=0A>=A0 >=A0= I did replace my cable the other day from Cat-5 shielded cable to a RCA=0A= >=A0 >=A0 cable that is also shielded. But with the Cat-5 cable I did not g= et=0A>=A0 >=A0 electronic noise. But with the RCA cable I do. I rather do n= ot want to=0A>=A0 >=A0 switch back to the Cat-5 cable, as it is harder to m= anage.=0A>=A0 >=0A>=A0 >=A0 What might be the reason why I am seeing electr= onic noise on the RCA=0A>=A0 >=A0 cable ?=0A>=A0 >=0A>=A0 >=A0 Regards,=0A>= =A0 >=A0 -- =0A>=A0 >=A0 J=F3n Fr=EDmann J=F3nsson=0A>=A0 >=0A>=A0 >=A0 ___= _______________________________________________________=0A>=A0 >=0A>=A0 >= =A0 Public Seismic Network Mailing List (PSN-L)=0A>=A0 >=0A>=A0 >=A0 To lea= ve this list email PSN-L-REQUEST@.............. with=0A>=A0 >=A0 the body o= f the message (first line only): unsubscribe=0A>=A0 >=A0 See http://www.sei= smicnet.com/maillist.html for more information.=0A>=A0 >=0A>=0A>=A0 _______= ___________________________________________________=0A>=0A>=A0 Public Seism= ic Network Mailing List (PSN-L)=0A>=0A>=A0 To leave this list email PSN-L-R= EQUEST@.............. with=0A>=A0 the body of the message (first line only)= : unsubscribe=0A>=A0 See http://www.seismicnet.com/maillist.html for more i= nformation.=0A>=0A=0A=0A___________________________________________________= _______=0A=0APublic Seismic Network Mailing List (PSN-L)=0A=0ATo leave this= list email PSN-L-REQUEST@.............. with =0Athe body of the message (f= irst line only): unsubscribe=0ASee http://www.seismicnet.com/maillist.html = =0A
=0A=0A
=0AFrom:= B> Geoffrey <gmvoeth@...........>
To: psn-l@..............
Sent: Tue, May 18, 2010 10:35:45 AM
Subject: Re: Electronic noise
I = was assuming electrical noise of any type.
Just about any KIND of noise = can be handled
in a similar fashion by tying eveything
together to be= ISO-Whatever.
If two of the same kind and value of resistors
are cha= nged in temp identically then the chage
should be somewhat invisible.
Like if EVERYTHING is 3C how would you even
tell it is 3C except th= at there is a mystry pressure
causing an invisible accelerational pressu= re force if the gas into
a great nothing nothing. In another 16 billion = years it might
be only 1.5c but that pressure will still be there if
= there is any temperature however slight.
If any of that makes any sense to anyone.
Li= ke hey man like, PV=3DnRT or something like that ??
----- Origin= al Message -----
From: "GPayton" <gpayton@.............&g= t;
To: <psn-l@..............>
Sent: Friday, May 14, 20= 10 10:10 AM
Subject: Re: Electronic noise
> Good informati= on and suggestions. However, I don't believe that Jon
> mention= ed the SOURCE of his interference or the DISTANCE of his needed run.
>= ; Both are important factors to consider.
> Regards,
> Jerry
>
> ----- Original Message -----
> From: Geoff= rey
> To: psn-l@..............
> Sent: Fri= day, May 14, 2010 12:02 PM
> Subject: Re: Electronic noise
><= BR>>
> At the local hardware store ACE BEST or whatever
&= gt; I found a signal cable suitable for underground buriel
>&nb= sp; which has some kind of grease impregnated beween the shield
>&nbs= p; and the cable jacket to keep moisure out.
> I installed a 40= foot run of it several years ago
> and it still seems good. Th= e shield is heavy copper foil
> which makes the cable not as fl= exable as it might be with
> a braided shield. You just need to= shield the jacket from sunlight
> everywhere it might be above= ground.
>
> Also you should avoid what is called ground = loops
> which can indice unwanted noise inside the cable
>= ; this can be avoided by choosing your gound
> and making= sure the shield is broken at one side of the connection
> or another to eliminate a DC path. I will typical= ly
> break the shield on the side opposite of the
> = side chosen as the primary ground.
>
> DC/LOW FREQUENCIE= S will travel deep within a conductor.
> But like over 1 MHZ th= e current exhibits a skin effect
> and only travels like within= the first 1/8 inch of the surface
> with that skin getting sma= ller/thinner as the frequency increases.
>
> I shoiuld im= agine the impedance is also related to this skin effect.
>
>&nb= sp; It seems to play a role in antenna design visible as gamma matching.
>
> Coaxial cable would be quite suitable for low frequenci= es
> if 100% shielded and have a proper BALUNS to keep
>&= nbsp; RF out of the inside of the cable.
> A BALUNS may be as s= imple as a series of
> FERRITE beads at the open ends of the shield.
> The broader the frequency block the more=
> beads you need and they are not cheap.
> They co= me in sizes for one wire or a whole 1/4 inch cable
> as a split= bead. I have seen them at Radsio Shack
> in the past.
>&= nbsp; You want to make sure what flows on the outside of a coax
>&nbs= p; does not leak into the inside. And, Vice Versa.
>
>
>&= nbsp; ----- Original Message -----
> From: "GPayton" <gpayton@.............>
> To: <psn-l@webtronics= ..com>
> Sent: Wednesday, May 12, 2010 5:16 PM
>&nb= sp; Subject: Re: Electronic noise
>
>
> > Jon, i= n the past I have observed that RCA type (audio) cable may not
> have
> > complete shielding; some ever have had a small thr= ead of wires and
> called it
> > shielded.
>&nbs= p; >
> > You might try coaxial cable.
> ><= BR>> > Regards,
> > Jerry
> >
= > > ----- Original Message -----
> > = ; From: J=F3n Fr=EDmann
> > To: PSN-Postlist
>&n= bsp; > Sent: Wednesday, May 12, 2010 7:09 PM
> >&nb= sp; Subject: Electronic noise
> >
> >
>= > Hi all,
> >
> > I did= replace my cable the other day from Cat-5 shielded cable to a RCA
>&= nbsp; > cable that is also shielded. But with the Cat-5 cable I di= d 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.
> >
>&nbs= p; > What might be the reason why I am seeing electronic noise on = the RCA
> > cable ?
> >
> &= gt; Regards,
> > --
> > J= =F3n Fr=EDmann J=F3nsson
> >
> > ______= ____________________________________________________
> >
= > > Public Seismic Network Mailing List (PSN-L)
>&n= bsp; >
> > To leave this list email PSN-L-REQUEST@.............. with
> > the bo= dy of the message (first line only): unsubscribe
> > S= ee http://www.seismicnet.com/maillist.html for more information.
>&nb= sp; >
>
> __________________________________________________________
>
>= Public Seismic Network Mailing List (PSN-L)
>
> To= leave this list email PSN-L-REQUEST@.............. with
> the body of the message (first line only): unsubscribe=
> See http://www.seismicnet.com/maillist.html for more informatio= n.
>
_____________________________________________________= _____
Public Seismic Network Mailing List (PSN-L)
To leave th= is list email PSN-L-REQUEST@.............. with the body of the message (first line only): unsubscribe
See http://www.seismicnet.com/maillist.html for more infor=[ Top ] [ Back ] [ Home Page ]