PSN-L Email List Message

Subject: Re: Electronic noise
From: John Cole johncole0722@.......
Date: Tue, 18 May 2010 21:03:36 -0700 (PDT)


=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: 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.
>


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