Rotel

Thanks everyone, Ive had the receiver for longer now, and im pretty much convinced its just some sort of RFI, since it does it really loud and obviously whenever anything is switched on or off (like light switches, the fridge motor, etc). The times when it was really bad, with no apparent cause, i have linked to the washing machine which (when its set to gentle action) turns on and off the motor every 10 or so seconds. The washing machine is downstairs in a different building approx 15 metres away. The reciever seems to be working fine in every other respect, but it is many times more sensitive to this type of interference than any other piece of audio equipment i have ever owned (and there has been lots). So this should help to identify the problem, perhaps?? perhaps there is a capacitor or something that is meant to filter out these types of transients??, that is faulty? I have the service manual for it and a CRO (though a really old one that has been under the house for years), though my electronics isnt up to that of a proper repair tech. I might consider getting it looked at , maybe, though now that i know what it is, it isnt nearly as annoying (eg knowing that when the washing machine has finished the noises will mostly stop). It would be nice to have it fixed , though.

Hi , I bought a Rotel RX-402 (combo amp/radio reciever) on eBay the other day, its got some annoying popping sounds in the preamp section somewhere. Does anyone have any ideas what it might be? Its not the power amp since you can disconnect the preamp from the power amp via RCA jumpers on the back so I could isolate each section. The pops are independant of what input is selected and of the control knobs (it does it at zero volume). When you are playing it loud you cant hear the pops but when you are playing something quietly, they are really annoying. Sometimes they are a lot worse than others. Ive tried turning off anything I thought might be causing RFI eg my computer, modem , etc, but no improvement. Sometimes you cant hear them at all. Which makes me think maybe its some sort of interference, though maybe also a defective component, or joint, or connection or something??? The volume of the pops varies randomly, when really bad They sound a little like the pops on a crackly vinyl record. It looks to me like the problem is in the final stages of the preamp section. Im happy doing basic electronic repair eg changing capacitors etc, though i am by no means an expert at reciever electronic tech. Im new to this forum, if there is another forum or group etc that would be better to post this question in, any advice on that would also be really appreciated.