I generally seek out the actual spec sheet on what I need to replace. I have seen NTE, ECG and SK books to be wrong.

I consider many things when choosing a replacement. If it is a switcher then I look at the turnoff time mainly if it runs into an inductive load. If it is analog I look at a few other things.

It seems like some of these "resources" do noyt consider all the parameters.. They for example had a replacement for an RCA 164589 diode which is a high speed rectifier. I told the boss "This is not going to work", he ordered me to put it in anyway and it lasted less than a minute. That was straight out of the ECG book, and NTE is a cheap knockoff on ECG. It is Nutone, ECG was Sylvania, SK is/was RCA.

The only way I'll take the word of a cross reference guide is if I got the JEDEC or JANTX numbers for the parts and can see the whole datasheet. those engineers don't waste money on a transistor when they could have used the old dime a dozen 2N3055. They get paid to save money, not to spend it.

So when you see a transistor that only has 50 volts across it and passes 2 amps, that doesn't mean that any transistor will work if it meets those specs.

For example, in a Zenith TV many years ago it had a funny looking picture. I found that in the IF module someone had replaced a video amp transistor with an RF power transistor. "WOW, this one'll do 50 MHZ, it must work !". Yeah, it worked but the picture looked like a cartoon because it was not linear in its gain. It was designed for use in a class C RF power output or driver circuit, not a linear amp.

Anyway, I trust nobody when it comes to replacements. If that thing breaks again it comes back on ME, and since the world is not really all that tolerant of my mistakes, I will do unto others.

Here's a project to test out this cross reference : change the outputs and drivers in a Marantz 1152DC. There's a test because you have to consider the Vbe before a transistor turns on and the Vcesat of the predrivers. The bias is not adjustable.

Who do you want picking your replacements then ?

At any time you can make a post here about a replacement and I will probably respond. Take advantage of that before something or someone kills me.