One of the BSX20 transistors has failed in my Cossor CDU 150 - the final part of the fault it had when I got it. Looking for a replacement I keep coming across transistors sold as BSX20 but in the specs it says "device marking 2N4401". This seems dodgy to me because these listings also state the case as TO18, but if I look for data on 2N4401 it is specified as TO92 and appears to be a bit more general purpose - in particular it has a much longer storage time and half the transition frequency. Real BSX20's are expensive (and I think they might not be made anymore), these ones are much cheaper.
Could someone enlighten me what is going on here? Or suggest a better substitute?
I put in a BC549 temporarily as the "least worst" tranny for the job in my junk box so at least the 'scope works now.