Newsgroups: rec.audio.tech
Subject: Re: Grounding problem: More information
References: <[email protected]> <[email protected]> <[email protected]> 
"N9WOS"  writes:

> > However, the two grounds should be the same (one is from the telephone
> > ground, the other from the 220 main feed, which is grounded no more than
> > about 10 feet from the telephone ground).
> 
> Do not hook up the radio ground to the telephone ground.
> 
> If it's anything like the telephone company around here.
> Your asking for it.

This varies from country to country, or maybe form are to area.
It is best to take a look at what the local regulations say. 

The practice of connect all grounds (power, telephone, antenna, etc.)
is very successfully used in many countries. I live in Finland where
this is mandatory practice in building. More details can be found at
http://documents.epanorama.net/documents/groundloop/electrical_wiring.html

In your countries ask the opinion of a qualitified electrician who 
knows the local regulations. If he/she says this "one common ground point"
practice is allowed practice in your case, I recommend to get that
electrician to do this kind of grounding properly to your house. 
Having a licensed electrician to do the connection will make sure 
that the work is properly safely done and the installer takes 
the responsibility that this is safe. This responsibility thing 
is necessary thign to consider in case somethign goes wrong for 
some reason (if you did it yourself it might be hard to convince 
for the insularance company that everyhting was done right and
according the the regulations after house has burned down)


> The only reason we don't have voltage differential problems is.
> The electric company has made it mandatory for the telephone
> company to fully ground their system on each power pole that
> they have their lines on.
> 
> The electric company has a ground wire on every pole.
> All hardware is bonded to it.
> 
> And they make the telephone company bond their messenger wire
> and other hardware to it.
> 
> But even at that. you want to avoid making a circuit between the two
> grounds at you house.
> 
> Because a loot of companies are not as strict as are local remc.
> 
> Some power companies don't even have guidelines for their own
> grounding methods. let alone the methods of the telephone company
> that uses their poles.
> 
> And around here.
> I've found that the telephone line, is the more likely path that
> lightning will come in on.
> 
> That's another reason to try to avoid hooking any stereo grounds to the telephone ground.
> 
> 
> 

-- 
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at 
http://www.epanorama.net/