Question about low-pass output filters for Bluetooth receivers
I wanted to replace my very old Bluetooth receiver (used for TV mostly) and bought some cheap Bluetooth receivers with a 3.5 mm phone jack.
Now it sounded a bit ..? not my idea of HiFi So scope on output.
2 Vpp out, OK But a 200 mV sinewave at about 350 kHz too, also when silent but paired. Some modules more than others. My old one is OK...
So simple lowpass RC? Any body have any experiences with that? I see a lot of papers on the subject when googling but all want me to sign in or whatever to access it.
I do get an annoying ringing in my ears after having listened to some music with that 350 kHz background. I know I am no bat, but then again... Using Sennheiser HD201 headphones or small earplugs.
Simple passive filer could work Or a parallel LC tuned to 350 kHz in series with the headphone (2 for stereo)?
Some people must have encountered this, or am Iteh only he fee bat here? Anyways fun project :-) This one I bought and is BAD