Re: Marconi 346 Radio
I've scoped the output with a 1k sine wave and it looks fine, I wonder now if the speaker has a problem with voice coil rubbing. I've attached a photo of the waveform and also noted that with the treble control on the lower two settings there is more hum which is making it sound more distorted, but the waveform still looks nice and free from distortion. These two treble capacitors I have replaced so it isn't a problem with leaky caps but I wonder where the exess hum is coming from with these two.
Strange though that the radio side of things seems to sound less distorted than the gram input. Next job is to connect a speaker to the external LS socket and see if that works okay, if it does then I suppose I'll need to source a replacement speaker unless this has an adjuster for coil seating.
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