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You Can Have My TIPs When You Pry Them From My Cold, Dead Hands
szczys writes: Should you trash brand new parts developed decades ago and adopt newer models? The argument centers around TIP parts which are a standard type of transistor developed in 1969. This debate started out with a post from Tom Jennings who is known as the creator of Fidonet but works a lot with electronic hardware. Adam Fabio — himself an Electronics Engineer — picked up on the argument for the other side. He attests that if used in the proper application these parts are second to none.
"Like people using ua741 opamps that are older than me. At least move into 1980 and use an LM358 or something. Same price or cheaper, and the input actually goes to one rail. Still very old junk, but significantly less so."
My favorite is the oldy-moldy OP-10. I happened to be interested in a _very_ low Input Impedance Op Amp at one time, (Not FET stuff...). Ten OP-10s in parallel brought the Input Impedance below 0.01 Ohms, and with some attention paid to topology, a linear sensitivity down to the 1:1 PicoAmp level. (This was for a Single-Turn Beam Transformer.) And it was fast, unlike most current Instrumentation Amplifiers, with the -3dB point at ~12KHz. Fast enough to see and tune out Ion Source noise. The typical technique back then- a lot of windings feeding a 50 Ohm cable and then into a 50m Ohm Terminator to derive a voltage, was and is hopelessly inefficient and noisy.
People are comfortable dealing with expected Impedance values, and most of the Literature unfortunately supports this.
I've gone to the opposite extreme on occasion; measuring the EV and Emittance, (Quantum Territory here...), of an individual accelerated Nucleon. The Nucleon exited the Detector pretty much unmolested. (Quick calculation here: ~10e22 Ohms.) This took advantage of not the Particle Information, but the Wave Information, and a whole lot of Liquid Helium.