Hello I have a problem with an Onkyo P306RS Preamplifier Everything works perfect on it accept when the input is set to phono the Left channel pops and hisses and blows the over protection on my Amp which is an Onkyo M-5030. It is only there when you turn up the volume and when nothing at all is connected to the phono Inputs its still there I connected my turntable and the right channel is fine but the left is just the Distortion seems to not be getting any signal input from the left input.Its got me stumped because it is only when it is on phono I haven't had it long i just didn't have a turntable so I never tried the Phono stage on it . Anyone have an idea where i would check for distortion on just he phono section it sounds like a leaking cap but this Preamp is pretty complex it shows in the service manual the phono section has 2 of the super servo circuits in it which are all in there own orange plastic cases under the Huge Metal Plate which is to just block out external distortion from outside devices etc. The plate weighs about 20 lbs and has a screw securing it to each or the Super Servo Amps like its a heat sink but it isnt the part it screws to are plastic. If anyone has any experience with these preamps it would be greatly appreciated if you could tell me where to start etc. And also i was wondering if an old 5mhz Scope would be good enough to possibly help in troubleshooting the older amps and preamps . All i have at the moment are two 5meg scopes ones a Ilco Model 460 and the other is a Heathkit IO-5205 lol, I'm Showing my age here lol. Any help would be appreciated.
Thank You!
Thank You!
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