|
New member Username: MichaeljoelPost Number: 1 Registered: Jun-05 | I have ground loop problem. I've read a ton about this and tried to troubleshoot it, but I'd just like some more advice before dropping $100 on an isolator. Here is my setup: Laptop, sending audio out to powered monitors (either direct to monitors, or through a small mixer, or through a firebox audio interface - makes no difference in hum) Pair of behringer powered monitors (speakers) Samsung 192mp LCD/TV monitor, NOT connected to cable, only to laptop Here is what happens: If everything is hooked up as above and plugged in, but the LCD monitor is turned off (but plugged in) there is a high pitched squeal coming out of the speakers. When I then turn on the LCD monitor, it turns into the low hum. This is the case even if I move the power supply of the LCD monitor (and the monitor itself) far away from the speakers and audio cables. No difference in volume of the hum either. This model LCD monitor also has a TV feature. When I switch it to that, so that it no longer takes any data from the computer, I get a fuzzy screen because I don't have it plugged in to cable, but the hum disappears almost entirely. From what people tell me it seems I need to buy an isolator for the LCD monitor - not the cable isolator but the electrical kind? Anyone have any idea what else I could do to troubleshoot or fix this? Thank so much in advance. |
|
Unregistered guest | MJ, Start by plugging your TV into a circuit that has nothing else using it. Sounds like you do have a ground problem IMO......If it was me that was having the problem the first thing that I would do would be to drive a ground rod in the ground where you could easily run some ground wires from the equipment you mentioned and to the rod. The cheapest and easiest way would be to dig a hole about a foot deep where you decide to drive the rod into the earth. I would take a copper coated or even a galvanized ground rod and drive it into the hole that you have dug......leave about 6 inches of rod above the bottom of the hole so when the hole is filled back in the rod will not be showing above ground level. Take and run a copper ground wire from each piece of equipment that you are using and connect it to the rod using a bronze clamp. Make sure you have a "chassis" connection on the equipment. You can buy these clamps at any Home Depot or electrical store and while you are there, buy a tube of "OX-Gard".....this stuff is the best dielectric there is. It will not only keep the connection free from corrosion but it will keep the connection "solid". When one uses 2 different kinds of metals and connects them together say like aluminum and copper or stainless steel and galvanize etc. electrolysis occurs (basically electrical action which corrodes),this Ox-Gard will keep that from happening. Connect all the equipment ground wires to the rod using a good amount of Ox-Gard smearing it and covering the rod and also the end of the wires. If your not making a mess then your not using enough. When all the wires are connected get some saltwater and poor it into the hole around the rod.....fill the hole and let it settle, then fill it again. Saltwater will make a good connection between earth and the rod.......if you live away from natural saltwater just mix up a batch of salt and tap water and use that. This should help if it is a ground problem but even if it isn't all your equipment should be grounded anyway and you will have a rod where you can connect ALL electrical pieces you have there and this should help out if you ever have a lightning strike. I really feel this should help and being very inexpensive (maybe $20.00) worth the effort. Good luck and hope it helps out......don't forget.....EVERY piece should be grounded. I would appreciate it if you would let me know if you received this message and how you made out with the problem. Good luck, Jerry J. ka1k@comcast.net |