Can someone help me identify what is the component on the central board that is burn. There is no number or any identification. Also any idea why it would burn, can it be just time (50 years). Thank you
It’s the output choke L100. Never seen one burn before. But it may be OK. Check it for continuity, and measure L if you can. Note that there is 10R in parallel so you can’t measure in circuit.
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Thread moved to Solid State.
I think i am going to install the new board and after restaure the old one so i am going to keep the original in working order
I would suspect a burnt output transistor, damaged driver transistor and possibly also damaged speaker. Best to check first before powering up
I am looking to change the two amp board. i am hesitating with Ferndale electronics, Motronix diode or Motronix transistor. Any advise ?
Motronix is proposing 2 differents type of board for the QUAD 303, one diode and the one transistor and ferndale is proposing diode. Wich one would you recommand and why ?
diode Motornix:
Transistor:
Ferndale electronics Diode:
diode Motornix:
Transistor:
Ferndale electronics Diode:
I suppose the ‘old diode version’ and ‘new transistor version’ refers to the biasing arrangement. Diode biasing was only used on the first 10-11,000 of the original Quad production run of 100,000. You don’t want that.
There isn’t enough information here to choose between the other two, if indeed there is any difference at all.
There isn’t enough information here to choose between the other two, if indeed there is any difference at all.
Ferndale boards based on issue 10 of the Quad 303 boards, I have used them a few times and work perfectly when the adjustments are set up correctly.