# The repair of a classic and the burden of new parts that are DEFECTIVE.



## audiogodz1 (Jan 5, 2010)

Anyone who has repaired anything electronics knows the suppliers don't always send new parts that work. I had that happen to me today on a 1st gen Punch 45 that I knew good and well just had a bad power supply transistor.

1:30 pm - Mail truck runs and drops off a (25) brand new bulk pack of TO-220's I've ordered to fix my 45.












1:50 - The amp is open and the bad transistor is replaced. Flip the switch on the 12v power supply and nothing happens. PS is in short circuit protection. Grab the Fluke and verify....... dead short across the + and - of the amp leads. 

2:10 - now TWO brand new (replaced the one on the other side) transistors in place, grab the Fluke...... still dead short. 

2:30 - having removed the diodes from the power supply near the transformer to verify there wasn't a bad diode and STILL having a dead short across the leads of the amp....... I'm getting that sinking feeling.


2:45 - I decide that I will start verifying the transistors I took out and I notice that they are both NPN and not one side being a PNp like I expected. I go back and pull the very first transistor that I replaced that started this whole mess that I knew was the only bad one in there and whadda ya know.... dead shorted. Damn defective part!!!!!

3:00 - I am listening to my Punch 45 and dancing around like I just won the lottery.

Moral of the story, we all know defective new parts are out there by the millions and we have all gotten them. Don't second guess yourself just because it is new, verify it before moving on.


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## Mangus (Jun 28, 2010)

Nice.

May I ask where do most of you folks order your new parts from? How quick a turn-around can one expect?

I've been able to get a few things at Radio Shack over the years but obviously their inventory is limited and seems to decrease yearly.

Thanks
Mangus


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