Inverter and PSU success
I am pleased to report my system is now entirely noise free from inverter/psu buzzing. How I hear you ask? By removing the phase correction circuit from the ATX power supply. This circuit exists just after the mains input and before the bridge rectifer circuits within a PSU and performs the task of filtering the incomming mains.. but with most inverters this filter circuit kicks up a fuss causing audible buzzing from the PSU and drawing excessive current.... a better explination can be found at the following sites
http://bjblaster.tripod.com/BjBlaster/power_supply.htm - BJ's web site
http://sproggy.mp3car.com/inverters.html - Sproggy's website
My system has been running for a while with the PSU unmodified and had only a slight buzzing in the output. I decided to remove the filter circuit today since I had some free time and anything that would drop the current drawn from the system would be good. Also the audible buzzing from the PSU seemed to be in tune with the buzzing from my speakers..... but this was a long shot.
..but to my suprise (yay!) the filter circuit WAS causing the last little bit of buzzing in the audio output.... powering the system back up removed the audible buzzing from the PSU and the noise from the speakers - perfect! And if your wondering the PSU/computer still run fine from the mains inside the house...
So if your running a inverter/PSU combo I would suggest you give it a shot. As explained a while back to me from BJ, most AT supplies have capacitors as the filters - these need to be removed, whilst modern ATX supplies seem to have a coil/choke instead along with a few ceramic capacitors. I just removed the ceramic capactors and the coil, replacing the coil with two wire links.....
anyway, sorry to rant and rave on, but this is good news for me, and hopefully others in the same situation. I took some happy snaps of the process on the digital camera - hopefully should have them up on my website in a few days.....
added a new page to my website with piccies of the procedure..... once again, if your running an inverter/PSU combo I 110% reccommend you give this a shot if you haven't already.......