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Question:

How to improvise a heat sink for a TO 39 transistor?

TO 39 is those small transistor that look like metal can, there isn't any where I can get the proper heat sinkCan I use a thick layer of aluminum foil?

Answer:

I always just spray mine with cookie spray and they come out everytime nice and easy and it is easier for the kids they don't have to pull off the wrapper
Parchment paper works wonders!
Ok, I just had to point out what a douche Mr Fat Cat isWOW Anyway, I just cooked cupcakes yesterday without the paper cupsI sprayed olive oil cooking spray on the sheet HEAVILY and they came out a bit dark on the outside where it touched the pan, but hardly noticable in taste, and they separated from the sheet just fineIf you want, you could even line the sheet with tin foil cups and spray THOSE with cooking sprayThat's what I would do if I had it to do againGood luck!
there is a good chance that if you don't have a 9 x 13 pan with 2 inch high sides to place all the cupcake papers together tightly in, then the batter will push the papers out and they will make a messPut the papers tightly together in the pan and then put the batter in them, good luckIcing: 1/2 cup softened butter, 8 oz of softened brick cream cheese, 5 cups of icing sugar, 1 teaspoon of vanillaMix all together with a wooden spoon or an electric mixer on low.
There are clip on heat sinks for that packageRemember that the can is connected electrically to the collector and may have voltage on it The reference has some, there are lots moreJust search for TO39 heat sink You need to start with a power dissipation in watts and from there calculates the heat sink you need in ?C/watt Thermal resistances add upIf your total power dissipated is 2 watts, for example, and the max junction temperature of the transistor is 200?C and the max ambient is 40?C, then the total thermal resistance has to be less than 160?C/2w or 80?C/wattThat means the sum of the thermal resistances have to add up to less than 80?C/wattThat includes that of the transistor, junction to case, that of thermal grease between the transistor and the heat sink (1?C/w) and that of the heat sin to air, which the manufacturer specifies Continuing the example, typical TO39 package parts are 60?C/w so the heat sink has to have a thermal resistance of less than 80–1–60 or 19?C/W .

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