Hi Everyone,
I have a curious problem that I'm hoping to get some input on. About 5 years ago I moved to a house that is right across the street from a radio broadcast tower. The radio tower broadcasts FM, cellular, and I'm told, many other types of RF. I have experienced a number of add RF interference issues living here such as car remotes that don't work, garage door openers with reduced range, and I often pickup faint FM radio signals on audio equipment when on the upper level of my house. Fortunately my basement audio listening room seems to be largely immune to any unwanted radio signals (even my MC phono stage!).
For the last 20 years or so I have kept an basic integrated amplfier of some sort in my home office with a pair of mini-monitors on my desk for both music and media consumption through a PC; I typically leave the amp on at all times since I'm often in and out of my office multiple times throughout the day. In the time I've been in this house I've had at least 5 integrated amps die overnight while powered on in my office. I've changed the speakers several times, the PC, and the connection type (analog, toslink, USB), as well as power conditioners, so there's really nothing common about these failures other than me living in this location.
Does is seem plausable that some stray RF is sending these amps in to oscillation and a premature death? If so, is there anything I might look for in an amp to avoid these issues (class D have been more reliable, and never seem to play audible FM)? Would shielding on cables or some type of filter or zobel network on the inputs / outputs offer protection?
The good news in all of this is that I have a stack of dead amps that I can use for amplifier repair practice.
Any thoughts on this will be appreciated!
I have a curious problem that I'm hoping to get some input on. About 5 years ago I moved to a house that is right across the street from a radio broadcast tower. The radio tower broadcasts FM, cellular, and I'm told, many other types of RF. I have experienced a number of add RF interference issues living here such as car remotes that don't work, garage door openers with reduced range, and I often pickup faint FM radio signals on audio equipment when on the upper level of my house. Fortunately my basement audio listening room seems to be largely immune to any unwanted radio signals (even my MC phono stage!).
For the last 20 years or so I have kept an basic integrated amplfier of some sort in my home office with a pair of mini-monitors on my desk for both music and media consumption through a PC; I typically leave the amp on at all times since I'm often in and out of my office multiple times throughout the day. In the time I've been in this house I've had at least 5 integrated amps die overnight while powered on in my office. I've changed the speakers several times, the PC, and the connection type (analog, toslink, USB), as well as power conditioners, so there's really nothing common about these failures other than me living in this location.
Does is seem plausable that some stray RF is sending these amps in to oscillation and a premature death? If so, is there anything I might look for in an amp to avoid these issues (class D have been more reliable, and never seem to play audible FM)? Would shielding on cables or some type of filter or zobel network on the inputs / outputs offer protection?
The good news in all of this is that I have a stack of dead amps that I can use for amplifier repair practice.
Any thoughts on this will be appreciated!
If it's doing that , what health effects does it have ?
Older hi-fi has no RFI filtering at all , some have a simple cap ... none of the old ones have CM chokes . etc.
No one had any SMPS chargers/PC's then.
Short of putting everything into a faraday cage (big metal grounded box) , your in a hard situation.
OS
Older hi-fi has no RFI filtering at all , some have a simple cap ... none of the old ones have CM chokes . etc.
No one had any SMPS chargers/PC's then.
Short of putting everything into a faraday cage (big metal grounded box) , your in a hard situation.
OS
Electrically , most amps have a hard input filter ... no >1mhz admitted. Typical Cdom on a AB amp will also reject < unity gain on RF.
A "dumb" linear power supply will also fully reject RF , older diodes can not switch fast enough and the EM field can't react fast enough,
OS
A "dumb" linear power supply will also fully reject RF , older diodes can not switch fast enough and the EM field can't react fast enough,
OS
