Does transistor package matter for the same part number? I have to replace 4 of the same transistor (one testing bad and better safe than sorry on the others). I purchased NOS replacements, but ended up with 2 different packages. One is the standard TO-92 and the other I can't find and it looks to me like a water tower. It's flat on the bottom, but had a dome to it. They have the same part number. Just wondering what's the difference, if any.

Also, I have NOS TO-39 transistors I want to install so I can reinstalled the factory heat sinks and retainer. Currently there are TO-220 installed, but no heat sinks and just freestanding. I put clip on heatsinks just in case, but I don't know if the 220s are better than the 39s. They are the video output transistors and are around 140V. I know the set came with the 39s as they were included in a bag when I bought the set and test fine.

Make that 3 different packages. See attached.

I can tell you the one on the left is your best option, despite the same silicon junction inside, the dome-top packages are not a favorite of Shango.

I can tell you the one on the left is your best option, despite the same silicon junction inside, the dome-top packages are not a favorite of Shango.

I guess I'll keep the others as emergency type replacements.

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The one on the right, and center are just older packaging. As long as they test ok,
and have the same specs they should be fine... Or possibly better since older
stuff typically had beefier margins on their design specs.... + Nice bigger
package probably had better heat dissipation.... Even though it was into
a poor conductor like plastic....

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