Just when you think you've seen everything.
Found a bad final transistor in a RCI2990DX. There was no heat sink compound between the ceramic insulating washer and the heat sink. But the washer was glued to the transistor with white bathtub caulk. I guess somebody told the weekend warrior to put some silicone on the new part when installing it. A tube of RTV rubber in the hardware store will clearly say "silicone" on the package.
Looks like I should have backed the camera away and zoomed in more. Depth of field isn't quite right here.
This was clearly a counterfeit transistor. Has the Mitsubishi "three diamonds" logo, but the package is the wrong size. A Mitsubishi part would be 9 mm wide. This one is the standard 10mm everybody else uses for this type package. Doesn't mean it was a bad part. It's a counterfeit that worked, or so said the customer.
Until the heat caught up with it.
Somebody should have explained to this guy what kind of silicone to use. And where to put it, for that matter.
73
Found a bad final transistor in a RCI2990DX. There was no heat sink compound between the ceramic insulating washer and the heat sink. But the washer was glued to the transistor with white bathtub caulk. I guess somebody told the weekend warrior to put some silicone on the new part when installing it. A tube of RTV rubber in the hardware store will clearly say "silicone" on the package.
Looks like I should have backed the camera away and zoomed in more. Depth of field isn't quite right here.
This was clearly a counterfeit transistor. Has the Mitsubishi "three diamonds" logo, but the package is the wrong size. A Mitsubishi part would be 9 mm wide. This one is the standard 10mm everybody else uses for this type package. Doesn't mean it was a bad part. It's a counterfeit that worked, or so said the customer.
Until the heat caught up with it.
Somebody should have explained to this guy what kind of silicone to use. And where to put it, for that matter.
73
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