Total noob with blown Pre-amp

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Keep hitting refresh on the page 🙂

Solder braid is used to make removing parts easy. It's a copper braided wire soaked on flux. You apply the hot iron to braid and joint to unsolder and the braid "wicks" the solder up instantly.
 
Snip the diode where the cross is
 

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C is pin 4 on the IC... the corner one. So there is a problem... possibly just the 79L15 that has been zapped by the failing diode. Other possibilities are that an IC has been damaged but that's the least likely tbh.

I'm going to have to call it night but I'm putting some notes down for you to follow... it's the easisest way as it enables you to keep referring back and then it will start to make sense.
 
Nothing else for soldering.

I'll post the notes shortly, then it should make sense. Can you post the type number on the IC's. I see two are 4580'S can't make the others out. It's just in case there is a faulty one.

The secret of fault finding is to narrow the problem down by measurement and test... cutting the diode was a worthwhile guess... but it wasnt that... so now we do it properly 🙂

The snipped diode can be replaced with one of the 1N4002's

I'll post shortly...
 
That's what I'm doing 🙂

Ultimately this is most likely the reg that is duff, and maybe the blue diode (zener) could have been taken out by all this, and finally one of the IC's.

Can you tell me the numbers on that diode ? in case we need a new one.
 
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