A Randall amp RG1503 amp came in sounding awful. I found the entire chassis was very sensitive to touch, it made it do all kinds of things. I put some torque on one of the big filter caps, and poof!, a little 4.7 ohm resistor went up in smoke. Odd. Upon measuring the output section I found an in circuit short on one side. I started to unsolder the power transistor, and the legs, one after another fell away. I pulled them from the heat sink, and all four have broken legs. They appear to measure fine, but I can't in good conscience try to solder them back like this. I did find an apparent short in one of the driver transistors, a 2SA1837.
Now the problem is, none of them are available any longer as far as I can tell. They are all over ebay of course, but I try to avoid those. What I need is two pairs of 2SA1941/2SC5198 and a pair of 2SA1837/2SC4793. I have read on another audio site that 2SA1942/2SC5200 will work, and Mouser has those. Can someone confirm this? I have never been to great at cross referencing semiconductors.
And what could I use for the driver pair?
Now the problem is, none of them are available any longer as far as I can tell. They are all over ebay of course, but I try to avoid those. What I need is two pairs of 2SA1941/2SC5198 and a pair of 2SA1837/2SC4793. I have read on another audio site that 2SA1942/2SC5200 will work, and Mouser has those. Can someone confirm this? I have never been to great at cross referencing semiconductors.
And what could I use for the driver pair?
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