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pcdubay
09-04-2003, 06:58 PM
A simple question...

Could be simple...who knows?

When I reach over and around my GXCEBOT to remove or replace anything on the back, (ie..cable, input, card, etc...) I seem to be getting a slight shock from my tivo case...oouch!

I visibly checked the power input cable for any signs of wear and such but see nothing unusual...

Anyone come across this before?

Thanks

GREEK
09-04-2003, 08:53 PM
if the cover is off you can feel the static and power around the power supply. If the covre is on, thats weird. Someone posted about this before, but I never saw anything like it before.

TheWickedPriest
09-04-2003, 10:24 PM
I've felt current from two HDVR2 units (mine and my sister's), with their cases on. IIRC, it was in the area of the RF in/out. Nasty.

Of course I've since realized that I should unplug the thing before I touch it, not just to avoid electric shock to myself, but to avoid potential trauma to the hard drive from impact shock.

okleydokley
09-05-2003, 07:21 PM
check your power plug. Is it keyed (can only be plugged in one way), or is it just an oval and able to be plugged in either direction?
If it is not keyed, run over to rat shack and get one that is. they are only about $3 and worth the possible fire hazard.

Gill
09-08-2003, 01:21 PM
I've noticed the same thing on my DSR6K. (yes this is with the cover in place) It only happens when I have my arm resting on part of it and plug in the LNB connectors. Example...reaching around with my forearm touching the back corner and attaching the coax cables for the LNB.

One thing I've found that prevents it is to unplug the cables going to the dish at the wall, before messing with any of the cables in back.

Good luck,
Gill

pcdubay
09-08-2003, 02:52 PM
WOW>>>
Nice replies...

Only had this happen to one of my tivo's thus far
happens when reaching over from the front (closed case)to change out my card
...and with bare feet
I would stand on a towel or put shoes on...

It is original power cord (only goes one way)

must be a grounding issue with the unit (something not grounded)

LazyBastard
10-06-2003, 04:40 PM
1) The case of the TiVo is connected to ground. If you have been walking across carpet you may get yourself statically charged. Touch the TiVo and you will discharge into it. Same thing if you touch the case of any computer or the metal case of any electronics.

2) The coax is powered - 20 volts with enough juice that you can sometimes feel it. If you touch the end while touching anything grounded *while* plugging it in, then the hot (inner) goes up through the LNB and back into the connector in your hand, through your body, and into the chassis. The way to solve this is simple - shorten the core so that it won't connect until it has been screwed in.

3) Your TV is statically charged. If your hair rubs the screen while you have your hand on the TiVo, you may get zapped.

Ingineer
10-11-2003, 09:52 PM
Because the TiVo is NOT grounded, it has a high-impeadance path from the chassis to the neutral side of the AC line. This provides a ground for static, but it can also cause small amounts of leakage current that you can feel under the right conditions.

Also, sometimes other devices in your system are providing small amounts of AC due to ground differentials. For example, if you have Cable TV, the incoming Cable line can have a ground differential. This can cause hum-bars in video and buzzing in audio if it's bad enough, and can usually be felt.

These are both common for almost all comsumer electronics. If you are concerned, add a solid earth ground to your TiVo and the associated electronics. A Star-ground topology is best. (ground your Coax inputs and all equipment to a central shared grounding point. The screw on your AC outlet will usually suffice)

LazyBastard
10-13-2003, 07:07 PM
Neutral and ground are the same thing.

It IS grounded.

BubbleLamp
10-13-2003, 07:58 PM
Originally posted by LazyBastard
Neutral and ground are the same thing.

It IS grounded.

Neutral and ground are not the same thing.

LazyBastard
10-13-2003, 10:40 PM
Try this:

Power a saw against live (black) and ground. It will work just like hooking it up to black and white.

Follow the wires. The ground and neutral are connected together SOMEWHERE - sometimes in the fuse panel, sometimes at the meter, sometimes at the road. ALWAYS connected.

Connect an ohmmeter between ground and neutral. Notice 0 resistance.

BubbleLamp
10-13-2003, 11:04 PM
Originally posted by LazyBastard
Try this:

Power a saw against live (black) and ground. It will work just like hooking it up to black and white.

Follow the wires. The ground and neutral are connected together SOMEWHERE - sometimes in the fuse panel, sometimes at the meter, sometimes at the road. ALWAYS connected.

Connect an ohmmeter between ground and neutral. Notice 0 resistance.

Nope, you're wrong. Here's one quick reference (http://www.ab.com/drives/techpapers/rfignds.htm)

And

another (http://www.nhml.com/news/articles/grounds1.htm)

and one

more (http://www.kennedyelectric.com/SureTest/Suretest-WhatIsAFalseGround.htm)

and one last one (http://www.svconline.com/ar/avinstall_neutral_ground_2/) that discusses the issue of ground loops and hum in stereo equipment.

LazyBastard
10-13-2003, 11:09 PM
LMAO. Did you even read those?

This image is from one of YOUR links:
http://www.nhml.com/images/groundsfig2.gif

BubbleLamp
10-13-2003, 11:12 PM
Originally posted by LazyBastard
LMAO. Did you even read those?

This image is from one of YOUR links:
http://www.nhml.com/images/groundsfig2.gif

You're the one who still doesn't get it. They are NOT the same. If they were, there'd be no need for the third ground wire. I sure hope you don't make a living as an electrician.:rolleyes:

LazyBastard
10-13-2003, 11:32 PM
READ what you posted. Some of that information is very good.

Have you noticed that things don't need a ground to work? Desk lamp... TiVo... etc.

The ground is there as a matter of safety. For example... if the neutral line breaks - then the live wire connects directly to chassis - lets say on your refrigerator. If YOU are touching the door handle of the fridge at the same time as you are touching a pot on the stove while this problem exists... if the fridge wasn't grounded, you'd feel it.

Yes, ground is a good thing! It keeps you from becoming toast. It keeps your house from burning down. This is because the *function* of the "neutral" is separated from the "ground". If everybody just started connecting their neutral to the ground wire, the failsafe value of the ground would disappear.

Just because the function is NOT separated on the TiVo doesn't mean that its not grounded. THE NEUTRAL IS CONNECTED TO GROUND, therefore it IS GROUNDED. See picture. Just has no failsafe, so if the neutral wire broke and you put your hand on both your TiVo and your VCR, then you would feel it.

BubbleLamp
10-14-2003, 12:12 AM
Originally posted by LazyBastard
Just because the function is NOT separated on the TiVo doesn't mean that its not grounded. THE NEUTRAL IS CONNECTED TO GROUND, therefore it IS GROUNDED. See picture. Just has no failsafe, so if the neutral wire broke and you put your hand on both your TiVo and your VCR, then you would feel it.

Wrong, there is no direct connection between EITHER leg of the power supply feeds and the chassis of the Tivo, go put a meter on it. Ingineer is correct, it is NOT grounded. Your misguided conclusion is that because one leg of the power MIGHT be tied to ground, the Tivo itself is grounded. Nope.

LazyBastard
10-14-2003, 09:27 AM
Its connected to ground through a board mount.