[cctalk] Re: Replacements for DEC 3639

[Jon Elson via cctalk]

On 10/27/25 05:26, Christian Corti via cctalk wrote:
It seems that nowadays you can't get *any* replacement for 
failing DEC 3639 aka 2N3639 transistors. All parts are 
obsolete and unobtanium, e.g. 2N3640, PN3640, MMBT3640 and 
so on.

So, what can be used instead? The most important 
electrical parameter is the storage time. It needs to be 
*very* low, around 20-30 ns.

Oh, it apparently is Silicon.  So, an MPSH81 should really 
do well.

Jon