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🔌General Home Automation => Automating Your House => Troubleshooting Automation Problems => Topic started by: Brandt on January 04, 2011, 11:01:53 PM

Title: XPPF causes tv to hum
Post by: Brandt on January 04, 2011, 11:01:53 PM

The XPPF hooked up to my 42" sharp aquos LED tv causes it to hum. It's been humming for a while before I looked into it so I don't recall if it has always hummed with the XPPF or if it had gone bad.

Title: Re: XPPF causes tv to hum
Post by: JeffVolp on January 05, 2011, 09:12:56 AM

Maybe it forgot the words...

Sorry, just had to do that.  Anyway, the XPPF is a low-pass filter.  Aside from some slight DC resistance, which would be similar to a moderate length of house wiring, it should have virtually no effect to 60Hz AC.  Since the XPPF has a couple of inductors that carry the load current, it is possible that the magnetic field is causing the XPPF inductors to buzz.  Another possibility is that if your TV power supply sucks in high current spikes, the XPPF could reduce the risetime of those spikes as it cleans up the noise the TV is presenting to the powerline.

Jeff

Title: Re: XPPF causes tv to hum
Post by: dave w on January 05, 2011, 09:29:12 AM

Quote from: JeffVolp on January 05, 2011, 09:12:56 AM

Maybe it forgot the words...

rofl