Hayd 0 Posted February 10, 2004 Report Share Posted February 10, 2004 When I power -up my laptop I get noise on the outputs from my mixers ( even with the faders on zero. I also get it while moving the mouse about and opening and closing software. Sort of a quiet morse code like sound, I get if when using either soundcards on the laptop and any input to the mixer. When there's music playing you don't notice it, just when it's quiet. Any idea how to stop this and if it's the laptop , mixer( KAM GMX5 ) or cables ? Hayd Link to post Share on other sites
The Spindoctor 0 Posted February 10, 2004 Report Share Posted February 10, 2004 Think this was covered before Hayd on another thread about laptops (might be worth searching those threads ) most likely culprit is your power supply to the laptop. Can't remember off hand which are worse than others but if you could supply that info too then I'm sure we will be able to help further. Spin Link to post Share on other sites
ChrisPointon 0 Posted February 10, 2004 Report Share Posted February 10, 2004 Yep - almost exact word for word description of another members' laptop problems. The solution? - new PSU for the laptop. http://www.dj-forum.co.uk/html/emoticons/smile.gif Link to post Share on other sites
Hayd 0 Posted February 11, 2004 Author Report Share Posted February 11, 2004 Thanks guys, now you mention it I seem to remember only noticing it with the power supply in. I 'll get a new one, is there a recommended one ? It#s for a Compaq Evo N1015v Cheers Hayd Link to post Share on other sites
ChrisPointon 0 Posted February 11, 2004 Report Share Posted February 11, 2004 QUOTE (Hayd @ Feb 11 2004, 06:11 AM) Thanks guys, now you mention it I seem to remember only noticing it with the power supply in. I 'll get a new one, is there a recommended one ? It#s for a Compaq Evo N1015v Cheers Hayd Most Laptops work on a voltage of around 16 - 20v dc @ 2.3 - 3.5 Amps. It's also fairly safe to assume that due to the nature of internal regulation circuitry that a laptop will still work correctly and safely from a PSU rated 0.5v - 1v HIGHER than its original PSU. So for example, plugging in an 18v PSU to a laptop rated at 17.5v will work safetly, provided you don't go above 1V difference http://www.dj-forum.co.uk/html/emoticons/excl.gif . Also make sure that connector and polarity of the connector is correct for your laptop. So, most generic PSU rated equal to, or very slightly above the voltage / current rating of the existing one will work okay. Ebay is a good source of replacement laptop PSU's http://www.dj-forum.co.uk/html/emoticons/smile.gif Link to post Share on other sites
DJGAVT 0 Posted February 11, 2004 Report Share Posted February 11, 2004 There is also a quick fix which is to just take out the earth wire from the plug http://www.dj-forum.co.uk/html/emoticons/stupid.gif Link to post Share on other sites
High Fidelity 0 Posted February 11, 2004 Report Share Posted February 11, 2004 QUOTE There is also a quick fix which is to just take out the earth wire from the plug http://www.dj-forum.co.uk/html/emoticons/fear.gif http://www.dj-forum.co.uk/html/emoticons/fear.gif http://www.dj-forum.co.uk/html/emoticons/fear.gif http://www.dj-forum.co.uk/html/emoticons/fear.gif That was a joke, wasn't it. Quitting Smoking & Drinking doesn't make you live longer It just feels like it. Link to post Share on other sites
SyC 0 Posted February 11, 2004 Report Share Posted February 11, 2004 Before you go out and buy a new power supply..... Try running the Laptop from a completely different power point than where your equipment is plugged in. We've found there is a problem like this when using extension cables or four banks .:Simon:. .:VibeZ Music & Discos (Mobile Disco & Karaoke):. Link to post Share on other sites
DJGAVT 0 Posted February 11, 2004 Report Share Posted February 11, 2004 It does work but I am not suggesting you try it. http://www.dj-forum.co.uk/html/emoticons/excl.gif Link to post Share on other sites
Hayd 0 Posted February 11, 2004 Author Report Share Posted February 11, 2004 Thanks for the info , I'll try a few of these ideas and then get a new power supply if they fail :-) Hayd Link to post Share on other sites
ChrisPointon 0 Posted February 11, 2004 Report Share Posted February 11, 2004 Don't be tempted to do anything stupid like disconnecting earth wires similar to Sparky above, or there is a danger of looking like this.... http://www.dj-forum.co.uk/uploads/av-35.gif Link to post Share on other sites
DJGAVT 0 Posted February 11, 2004 Report Share Posted February 11, 2004 No don't do it but I hope people are sensible enough to know that Link to post Share on other sites
The Spindoctor 0 Posted February 12, 2004 Report Share Posted February 12, 2004 Apart from which these days most of the laptop power supplies don't have any earth lead to disconnect!!!!! Spin Link to post Share on other sites
adenondj 0 Posted February 12, 2004 Report Share Posted February 12, 2004 thankyou spin, most laptops cables dont have earth they have 'figure 8' cables to conect them to the power supply (wich have just live and neutral!) Paul ''king'' Denon D.J. for life Link to post Share on other sites
Melody_Roadshow 0 Posted February 12, 2004 Report Share Posted February 12, 2004 Is it a pulse / heartbeat type noise and have you used the laptop before with no problems http://www.dj-forum.co.uk/html/emoticons/smile.gif I ask because similar thing happened to me and it was to do with the settings of my sound card - had to install the proper drivers not let windows find its own Link to post Share on other sites
Hayd 0 Posted February 12, 2004 Author Report Share Posted February 12, 2004 Tried seperate, power sorce ( different ring ) no difference, disconnected the earth from the laptop transformer , instantly killed the noise. I'm sure un-earthing the transformer isn't the safest option but it's a solid lump so I can't see much chance of shock from it. Only Live and neutral go to laptop itself anyway. There is Zero noise now :-) Hayd Link to post Share on other sites
DJGAVT 0 Posted February 12, 2004 Report Share Posted February 12, 2004 Its because you get an earth loop I am yet to find another way of fixing it. And I was told its ok by a DJ Shop (and not a small one). Just passing on what I was told dont shoot the messanger http://www.dj-forum.co.uk/html/emoticons/fear.gif Link to post Share on other sites
High Fidelity 0 Posted February 13, 2004 Report Share Posted February 13, 2004 QUOTE Its because you get an earth loop I am yet to find another way of fixing it The safest way of overcoming earth loops is to use a DI (Direct Injection) box to connect signals to mixers or amps. I suffer from this all the time when setting sound systems up in theatres, even when running everyting from an isolated 32 amp line, so I always carry at least one. Hope this helps. Quitting Smoking & Drinking doesn't make you live longer It just feels like it. Link to post Share on other sites
ChrisPointon 0 Posted February 13, 2004 Report Share Posted February 13, 2004 QUOTE And I was told its ok by a DJ Shop (and not a small one). One of my local D.J shops (also a large business) employs non D.J's to serve during busy periods who probably wouldn't know what colour an Earth wire was! let alone be qualified Electricians. Try disconnecting the earth from your equipment when it next goes in for a PAT test and see the result. Take a look at the labels on most domestic appliances - often you'll find a label marked "This equipment must be earthed" - they don't put that on there to fill up space and use ink! - its on there because in some faults an earth wire can mean the difference between life an death. Let me explain how it works. The Earth wire connects between the metal casing / exposed metal parts of an appliance and connects through the socket into a ground point (usually a spike outside the building pushed into the ground, or the sheath of the armoured mains cable feeding the building). If a fault occured that meant that a live cable touched the metal casing of an appliance, then the entire metalwork of the appliance (and gantry in the case of lighting effects) would become live at 240v. If an Earth wire is connected correctly, then the wire conducts the mains voltage to "earth" causing the fuse in the mains plug to blow and break the circuit. If the earth wire is disconnected then this won't happen , meaning that the case of the appliance remains at 240V and will often continue to work. However if you (or anybody else) touches the live metal parts then the voltage will flow to earth via your body - which can immediately stop your heart and often proves fatal (Cue Casulty theme tune), or if your lucky you may get away with some very painful burns. Still worth the risk?. Sorry, but removing the Earth wire from any mains appliance is extremely dangerous and irresponsible, and a bit like rock climbing with your safety rope disconnected http://www.dj-forum.co.uk/html/emoticons/scared.gif . Perhaps you should ask this shop to put this advice in writing in order to cover yourself - then make your decision on how good and reliable it is based on their reaction:) . If you want genuine Electrical Safety advice - ask a qualified electrician, I wouldn't take advice on a Medical Condition from a Car Mechanic, and the same applies in this case!. Removing the Earth Wire is a lethal way of getting around a problem which carries a great risk, both to you an your audience, it is not a SOLUTION to the problem!. The safest way of overcoming earth loops, is to use better (Screened) cables, use earth-lift switches (where fitted) on Mixers and Amplifiers, or by buying a DI box as Paul suggested. Link to post Share on other sites
Hayd 0 Posted February 13, 2004 Author Report Share Posted February 13, 2004 Thanks for the info all, now that I know the earthing is the problem I see if I can source a DI box to solve the problem ( or better power supply ). Cheeers Hayd Link to post Share on other sites
High Fidelity 0 Posted February 13, 2004 Report Share Posted February 13, 2004 Having worked in the electrical/electronic industry for most of my working life, I have had more than my share of electric shocks. These have ranged from the standard 240volt variety up to the thousands of volt types found in televisions. One of these instances came from using some equipment that I had borrowed, and guess what!! http://www.dj-forum.co.uk/html/emoticons/fear.gif The person who owned the equipment had disconnected the earth wire in the plug. http://www.dj-forum.co.uk/html/emoticons/wallbash.gif http://www.dj-forum.co.uk/html/emoticons/wallbash.gif Here's a tip that could save your life. (But don't try it just to see if it works http://www.dj-forum.co.uk/html/emoticons/stupid.gif ) We'll assume an impossible set of circumstances (Well it should be impossible http://www.dj-forum.co.uk/html/emoticons/wacko.gif ) where the following happens. Due to some catastrophe, all your equipment develops a fault, (say a short circuit inside) which causes all the switches to fuse together and all the plugs to fuse into the sockets so you can't isolate your equipment from the mains. As part of this catastrophe your lighting rig topples over and somebody is pinned underneath it. Is the equipment still live http://www.dj-forum.co.uk/html/emoticons/533.gif electrocuting the person trapped under it? You've asked the caretaker/manager of the venue to shut off the power to the sockets feeding your equipment (but how much do you trust this person). The person trapped is in need of medical attention as quickly as possible. Assuming you haven't got a tester to check if the equipment is still live, what can you do. Did I hear someone say grab a coat or a chair to lift the equipment of the trapped person. Some clothing materials will conduct electricity, and if the person who has been wearing the coat has been sweating, although it may feel dry, there may well be enough moisture to conduct electricity. Likewise the varnish or paint on the chair could conduct, or may have absorbed enough moisture to conduct electricity. In this highly improbable situation, this is what I would do. (And have done in a slightly different situation to render first aid to someone.) Crouch next to the equipment so that you are unbalanced in such a way that if you fall you will fall away from the equipment. Then with a swinging arm movement, gently strike a bare metal part of the equipment with the BACK of your fingertips. The momentum of your arm makes sure that you do not stay in contact with the equipment and the fact that when you recieve an electric shock your muscles go into spasm. So your hand clenches, also pulling your fingers away from the equipment. The first rule of first aid is "Asses the situation with regard to your own safety". Quite right really as you can't help anybody if your dead. Electricity kills if not respected. So be safe. Use your own ELCB adapters, have your equipment PAT tested, and never ignore earth leads. So Hey, "Lets be careful out there". (Sure I've heard that on TV). http://www.dj-forum.co.uk/html/emoticons/thumbup.gif http://www.dj-forum.co.uk/html/emoticons/thumbup.gif Quitting Smoking & Drinking doesn't make you live longer It just feels like it. Link to post Share on other sites
C.S 0 Posted February 14, 2004 Report Share Posted February 14, 2004 Please listen to this man,very very good advice. I will try anything,once! The Cornish will arise again ! Manager of the Andy Harris Fan Club. Keep pasties Cornish Link to post Share on other sites
ChrisPointon 0 Posted April 4, 2004 Report Share Posted April 4, 2004 Posted with Picture on Behalf of Paul (HighFidelity)....... My new laptop gives me an earth loop, (the old one never did as it didn't have an earth wire on the power supply). Needing to sort this out quickly for the show that I've just finished doing, I visited my local electronics shop to see if they had a cheap 2 channel DI box. "No" said the man, "But you could try this. It's under a tenner and really does work". http://www.chrispointon.f2s.com/altai.jpg He was right! It works brilliantly. Don't know if Chris can get hold of these, but if he can I'm sure they would sell. Link to post Share on other sites
tonyj 0 Posted May 2, 2004 Report Share Posted May 2, 2004 i've just got one of this little "ground loop isolators" it works a treat... http://www.dj-forum.co.uk/html/emoticons/thumbup.gif http://www.dj-forum.co.uk/html/emoticons/thumbup.gif thanks another top tip from the DJU http://www.dj-forum.co.uk/html/emoticons/toot.gif Member of The Musicians Union "Opportunity is missed by most people because it is dressed in overalls and looks like hard work." Link to post Share on other sites
Hayd 0 Posted May 2, 2004 Author Report Share Posted May 2, 2004 Yep also done the same, great tip guys :-) Link to post Share on other sites
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