Thanks for another great video! The main reason that the "FSD" keeps going out , is the design of the aluminum case. It does not matter how efficient of a heat sink that one installs on the unit ,.The main problem is that there is too much thermal resistance from the mounting point of the TO3 type power transistors , to the actual externally mounted heat sink. Not only are the power transistors mounted wrong, so are the emitter resistors and the TO202 style driver transistor that drives the main TO3 style power transistors. I think that if the TO3 transistors were remotely mounted to another heat sink, These units would last much longer. I have a unit ready to test that theory. I will share the results with you if you wish. Your comments, agree or disagree, are welcome.
Thanks, yeah I'd agree the TO3s are the thermal weak point. I've successfully rebuilt them from time to time th-cam.com/video/GLjGUlCvFVM/w-d-xo.html to reduce their replacement costs, but would suspect when the one aftermarket supplier (Flight Systems) went thru their redesign, they likely could not find a replacement package that still performed to Stanadyne specification. Since Flight Systems were after being an GMSPO (GM service parts operations) approved supplier, that likely drove to keeping the TO3s.
Excellent video !! Another excellent video I must say!
Thanks for another great video! The main reason that the "FSD" keeps going out , is the design of the aluminum case. It does not matter how efficient of a heat sink that one installs on the unit ,.The main problem is that there is too much thermal resistance from the mounting point of the TO3 type power transistors , to the actual externally mounted heat sink. Not only are the power transistors mounted wrong, so are the emitter resistors and the TO202 style driver transistor that drives the main TO3 style power transistors. I think that if the TO3 transistors were remotely mounted to another heat sink, These units would last much longer. I have a unit ready to test that theory. I will share the results with you if you wish. Your comments, agree or disagree, are welcome.
Thanks, yeah I'd agree the TO3s are the thermal weak point. I've successfully rebuilt them from time to time th-cam.com/video/GLjGUlCvFVM/w-d-xo.html to reduce their replacement costs, but would suspect when the one aftermarket supplier (Flight Systems) went thru their redesign, they likely could not find a replacement package that still performed to Stanadyne specification. Since Flight Systems were after being an GMSPO (GM service parts operations) approved supplier, that likely drove to keeping the TO3s.
Great Advice!! Any thoughts on using heat sink compound instead of the thermal gasket?