John Curl's Blowtorch preamplifier part II

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If it says 36 V on the tin, that's as high as I'll be going.

A semiconductor is probably one of the most reliable pieces of engineering in the modern world - provided you stick within specifications and specifically absolute max ratings. I'd take a semi over a jet engine any day in a reliability competition (ok, I can see the flames coming 😀)

If you want higher voltage swing or more current, then design for it rather than stress a part beyond its quoted limits.

Why **** with perfection?
 
If it says 36 V on the tin, that's as high as I'll be going.

A semiconductor is probably one of the most reliable pieces of engineering in the modern world - provided you stick within specifications and specifically absolute max ratings. I'd take a semi over a jet engine any day in a reliability competition (ok, I can see the flames coming 😀)

If you want higher voltage swing or more current, then design for it rather than stress a part beyond its quoted limits.

Why **** with perfection?

Yeah - I don't see the point of overvolting it for no good reason....
 
One way trip eh?

😀

Laugh now I'll have the secret easter egg when Vger comes back. 😀 One of my last products as product engineer before design was the AD590 used as temperature monitors on the tiles for the space shuttle. You would not believe the data those parts went with everything had to be NIST traceable to .001 degree, then look at what happened.
 
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Not really unheard of, I've tested quite a few discrete transistors at voltages above their specified ratings and many a time, nothing happned, it worked on. This is especially true of Motorola/ON Semi's devices, which is why I have such a strong preference for them. I know I can really push them.

Lots of the moto product back in the late 80's would have bvces almost twice the part rating. I tested them on wafer. The company I worked for would many times, use the chips at voltages exceeding the spec, and select based on my testing data. 40 volt parts were tested to be used as a 60 volt part, getting around some of the design tradeoffs caused by using a 60 volt spec'd part.

That didn't always work. That is why I do not recommend using silicon past it's rating.

Reason 14 why I got out Aerospace. 10 years testing a part half to death then it blows up on you. But I believe that working with Mil 217-F gives you a couple of years off purgatory/whatever afterlife cleaning one believes in.

Using 217 IS purgatory.

Hey, has your offspring started work at that place yet?

John
 
Laugh now I'll have the secret easter egg when Vger comes back. 😀 One of my last products as product engineer before design was the AD590 used as temperature monitors on the tiles for the space shuttle. You would not believe the data those parts went with everything had to be NIST traceable to .001 degree, then look at what happened.


Yeah, the damn tiles go and fall off . . .

Separately, I lived in the US in 1986 in a place called Lakeland in Florida. We watched the Shuttle launch from the car park and saw it go to pieces.

Around that time we had and were supplying industrial temperature measuring instrumentation to Morton Thiokol for production. After it became clear the problem was with one of the boosters, I think our company's management sweated bricks for a few months until the root cause actually was found . . .
 
I like reading about the tubes, but part of me think you guys should shut up because otherwise we'll be reading about the latest amp with "same tubes as nuclear missiles!"
Recall why NMR is fine for chemistry and physics, but they have to call it MRI when it is a human body. "Nuclear" would not do.

And JBL Pro had to change the model number of their ill-fated power amp from SR6660 to SR6670. You can't make this stuff up.
 
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