On 19/04/2019 10:01 am, wrote:
Is there any way to test a STK463 Audio Amp chip? (without having some
sort of special factory analyzer)?

**Yep. Download a data sheet, build up the test circuit and test.
Alternatively, plug it into the existing product, crank the unit up on a
variable auto-transformer (aka: Variac„¢). Watch Voltages and currents
carefully.


I had a Marantz SR1000 receiver given to me. I plugged it in, and got a
few seconds of hum, panel lights dimmed also. Then smoke appeared. I
found the source of the smoke, a small electrolytic cap blew, and left
the board wet.

**Which cap? You could analyse the circuit and determine what is causing
the cap to fail (assuming it is not just the cap).


I may try to replace that cap, but I suspect there is more wrong. I dont
usually work on anything containing IC chips. And Im sure if that big
amp chip is bad, it would be very costly. (Not worth my time or money).
But I'd be willing to test it if I know how.

**"Big money"?!! Are you serious? They're like 10 Bucks. 10 minutes of
your time (using a vacuum desolder iron, or 20 minutes with a manual
one), job done. Easy-peasy. Back when I was service manager for Marantz
Australia, I replaced a hundred or so of the things. Not so reliable,
but easy to replace. No fault-finding required.


By the way, the power supply is working. As soon as I unplugged it
(after the smoke), I got a good spark when I shorted the main (large)
filter caps.

**Yeah, no. That ain't real smart either.


--
Trevor Wilson
www.rageaudio.com.au

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