Frank Otero Posted July 19, 2009 at 10:27 AM Posted July 19, 2009 at 10:27 AM I am operating from a location where electric power is not reliable; therefore, I use an inverter as a back up - 12vdc to 220vac 50Hz. It seems that when I am running on the inverter a humming sound is heard by those receiving my transmissions - either in VATSIM or Yahoo phone service. I do not hear this on my side, but can tell that the power supply to my laptop does seem to have a humming/vibrating sound of itself. I have done research on different filters, but would like to hear any suggestions from those who have faced this situation and/or have the expertise to address it. Because...... disconnecting the laptop power supply just before transmitting is heavily taxing my already limited piloting skills Thanks in advance Link to comment Share on other sites More sharing options...
Erhan Atesoglu 1050499 Posted July 19, 2009 at 07:37 PM Posted July 19, 2009 at 07:37 PM A USB headset should fix that problem easily...? http://www.pond64.net Link to comment Share on other sites More sharing options...
Richard Gerrish Posted July 20, 2009 at 12:08 AM Posted July 20, 2009 at 12:08 AM noise on your audio is caused by poorly shielded wiring, connectors, bad soldering jobs, grounding issues ect. if your laptop is a 2 pole + ground connector then you can try a ground lift. we use these at work in a variety of configurations http://news.thomasnet.com/fullstory/512808 good luck with the ground humm Richard Gerrish Developer, STM Applications Group Link to comment Share on other sites More sharing options...
Frank Otero Posted July 22, 2009 at 08:14 AM Author Posted July 22, 2009 at 08:14 AM Hi Richard, Thanks for the advice. I have definitely isolated the problem to the inverter while it is doing its thing converting 12vdc to 220vac, it just does not happen under other conditions. And when it does happen it is only noticeable to those on the receiving end of my transmission. The power supply to my laptop has a two-prong connector/plug (typical for the US). The system here, however, is european, which receives two-prong connectors (different shape than the US) and offers ground via contacts on the side of the connector/plug that meet ground contacts in the wall outlet. Therefore, although my inverter is grounded (well, it is plugged to ground), my laptop connector/plug cannot take advantage of this since it connects to power through an adaptor (due to the different shapes of the US to europe connector/plug) that does not provide ground. Actually, the same be true when I plug it at home, would it not? Since it is only a two-prong connector/plug. So, I am not sure how to provide ground to my laptop power supply. From what I have read, it seems that only the most advanced/expensive inverters produce "pure sine" electricity. I have read of some filters that correct this problem, but unfortunately at this moment my access to such devices is limited. Once again, thanks for your help. Link to comment Share on other sites More sharing options...
Richard Gerrish Posted July 22, 2009 at 07:41 PM Posted July 22, 2009 at 07:41 PM Hi Richard, Therefore, although my inverter is grounded (well, it is plugged to ground), my laptop connector/plug cannot take advantage of this since it connects to power through an adaptor (due to the different shapes of the US to europe connector/plug) that does not provide ground. Actually, the same be true when I plug it at home, would it not? Since it is only a two-prong connector/plug. you're quite correct even in the states on 120V your laptop would still be ungrounded. Some manufacturers used to use the 3 prong connector for their laptops. try this site. they have quite a few products that should help you out http://www.world-import.com/transformers.htm Richard Gerrish Developer, STM Applications Group Link to comment Share on other sites More sharing options...
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