|
07-03-2008, 06:49 PM
|
#1
|
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
Join Date: Jun 2006
Posts: 12,880
|
Groundless Laptop
I've been recording online videos (e.g. Hulu - Watch your favorites. Anytime. For free.) from the computer to the DVR. There was a 60 Hz hum in the audio, and from some Googling I found that I could eliminate it by using a three-prong adapter, that is, by eliminating the ground on the plug ( ground loop info).
I don't see any significant risks in running the laptop ungrounded, do you?
__________________
Al
|
|
|
|
Join the #1 Early Retirement and Financial Independence Forum Today - It's Totally Free!
Are you planning to be financially independent as early as possible so you can live life on your own terms? Discuss successful investing strategies, asset allocation models, tax strategies and other related topics in our online forum community. Our members range from young folks just starting their journey to financial independence, military retirees and even multimillionaires. No matter where you fit in you'll find that Early-Retirement.org is a great community to join. Best of all it's totally FREE!
You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with our members, see fewer ads, upload photographs, create a retirement blog, send private messages and so much, much more!
|
07-03-2008, 11:12 PM
|
#2
|
Thinks s/he gets paid by the post
Join Date: Feb 2003
Posts: 2,395
|
Quote:
Originally Posted by TromboneAl
I don't see any significant risks in running the laptop ungrounded, do you?
|
Ungrounded should be fine. But don't make it un-earthed, lest you be killed in a very prim and proper way
__________________
-- Telly, the D-I-Y guy --
Two fools dancing on the hands of time
|
|
|
07-04-2008, 09:19 PM
|
#3
|
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
Join Date: Sep 2005
Location: Northern IL
Posts: 26,806
|
One extra precaution - unplug the laptop power, then connect the video/audio cables to the video/audio system. Then plug the laptop power in.
Just a little extra insurance, in case the laptop 'floated' to a higher voltage above ground. If that happened, it would be the cable connection that would suddenly bring the laptop back to ground potential. That could put a bit of a zap into the laptop, or the audio/video system.
-ERD50
|
|
|
07-04-2008, 09:43 PM
|
#4
|
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
Join Date: Dec 2003
Location: Losing my whump
Posts: 22,708
|
Just dont stick it in the water
Sounds like you have a ground loop or an invalid earth ground.
Beyond that is a speculation about your cable companies installation and short and rusty ground rods.
__________________
Be fearful when others are greedy, and greedy when others are fearful. Just another form of "buy low, sell high" for those who have trouble with things. This rule is not universal. Do not buy a 1973 Pinto because everyone else is afraid of it.
|
|
|
07-05-2008, 12:56 AM
|
#5
|
Thinks s/he gets paid by the post
Join Date: Jul 2007
Posts: 2,487
|
They run fine without the ground. In some places in Asia, the chargers don't even have the third (grounding) prong. I bought a Sony Vaio for DW that doesn't have one. In fact, even if it had a third prong, there are lots of buildings here that do not have a receptacles that accept the grounding prong. I'm running my US bought Compaq right now without one (using an adapter) because there is no place to plug it otherwise.
R
|
|
|
07-05-2008, 07:31 AM
|
#6
|
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
Join Date: Oct 2005
Location: North Oregon Coast
Posts: 16,483
|
Quote:
Originally Posted by TromboneAl
I've been recording online videos (e.g. Hulu - Watch your favorites. Anytime. For free.) from the computer to the DVR. There was a 60 Hz hum in the audio, and from some Googling I found that I could eliminate it by using a three-prong adapter, that is, by eliminating the ground on the plug ( ground loop info).
I don't see any significant risks in running the laptop ungrounded, do you?
|
I'm assuming you wouldn't be doing this during a thunderstorm?
__________________
"Hey, for every ten dollars, that's another hour that I have to be in the work place. That's an hour of my life. And my life is a very finite thing. I have only 'x' number of hours left before I'm dead. So how do I want to use these hours of my life? Do I want to use them just spending it on more crap and more stuff, or do I want to start getting a handle on it and using my life more intelligently?" -- Joe Dominguez (1938 - 1997)
|
|
|
07-05-2008, 08:35 AM
|
#7
|
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
Join Date: Sep 2005
Location: Northern IL
Posts: 26,806
|
Quote:
Originally Posted by ziggy29
I'm assuming you wouldn't be doing this during a thunderstorm?
|
Probably should avoid plugged in electronics in a thunderstorm anyhow, but not any more/less dangerous w/wo the ground on the laptop PS.
The end result here is that the laptop *is* grounded. It is grounded through the audio/video cable ground. What he is doing is avoiding two grounds, which can cause the ground loop problems he linked to.
I'd assume that T-Al has run into this problem with his band? I seem to remember that some of my old amps had a 'ground lift' switch, for this exact purpose. But you do need to make sure that no outlets have hot-neutral reversed. That can be exciting (and deadly). Hands on metal guitar strings, lips to the metal wind screen on the mic - ouch!!!!!
-ERD50
|
|
|
07-05-2008, 09:51 AM
|
#8
|
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
Join Date: May 2008
Posts: 6,496
|
Chasing ground loops can be frustrating, often there is a ground loop between tv, DVR, Cable from street side to equipment. A frequent help is to isolate the cable with "balun" fancy name for for a transformer. Two of the 300 Ohm to 75 TV transformers connected with their 300 Ohm leads together, connected between cable and tv will kill one ground loop.
Cheching for hot/neutral reversals is important, as noted by others. Floating a laptop from house ground should be no problem.
__________________
There must be moderation in everything, including moderation.
|
|
|
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
|
|
Thread Tools |
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Threads
|
|
|
|
|
|
|
|
|
|
|
|
|
» Quick Links
|
|
|