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[on:]

around 8 years ago I used a 6 volt battery on a 1.5 volt motor to make it better I used my computers USB port in series with the battery. 3 seconds later the computer shut off and wouldn't turn back on. What could of happened to the computer as in what part do you think fried?

[Reply #1 on:]

I don't know, but it reminds me many years ago, at Data General in the period after the book Soul of a New Machine was set, we had a problem as they were developing the Eagle (MV/8000), that they would come out with new generations of the boards and upgrade the machines.

The lab manager noticed that every so often field circus would try to be helpful, and recycle the old out of spec boards into new computers, and didn't notice and thought the boards were good.  Finally the lab manager came up with what he called a circuit tester, which had a normal 110 A/C plug on one end, and two wires on the other end.  After he used the circuit tester, sure enough even field circus could verify that the board was bad.  

[Reply #2 on:]

Ever read the story of why Apollo 13 failed?
A catalogue of accidents and bad specs combined.

[Reply #3 on:]

I don't know, but it reminds me many years ago, at Data General in the period after the book Soul of a New Machine was set, we had a problem as they were developing the Eagle (MV/8000), that they would come out with new generations of the boards and upgrade the machines.

The lab manager noticed that every so often field circus would try to be helpful, and recycle the old out of spec boards into new computers, and didn't notice and thought the boards were good.  Finally the lab manager came up with what he called a circuit tester, which had a normal 110 A/C plug on one end, and two wires on the other end.  After he used the circuit tester, sure enough even field circus could verify that the board was bad.  

Field Circus? Heh, you're dating yourself there. The 1st Unix box I did any real work on was a DG. Don't remember what model. (Prior to that, my exposure was figuring out how to fix a tty port on a Vax running Ultrix, so UUCP would work again.)

That was a good book.

[Reply #4 on:]

Field Circus? Heh, you're dating yourself there. The 1st Unix box I did any real work on was a DG. Don't remember what model. (Prior to that, my exposure was figuring out how to fix a tty port on a Vax running Ultrix, so UUCP would work again.)

That was a good book.

The first UNIX box that they did was based on the Motorola 68000 that I'm not even sure ever shipped to customers.

The had a 'UNIX' skin over the AOS/VS operating system called MV/UX.  I wrote the front end for their C compiler and it was painful due to the MV/8000 (eagle) and later generations being rather hostile to the C language.

Then they did a full UNIX system on the MV/8000 called DG/UX, with the AOS/VS C compiler I worked on repackaged for the system.

Finally, they decided to move to the Motorola 88000 chipset, and I switched over and finished the GNU C compiler for the 88000, and called the system AViiON.

After I left Data General for greener pastures, they switched the AViiON from using the 88000 chipset to x86 processors.  Eventually EMC bought them primarily for the storage subsystem, and closed down the software side of things.

[Reply #5 on:]

Hehe - I have a 2-AA battery powered circuit tester. The last test for an USB stick made the stick explode. After the test it was absolutely clear that the stick was bad. --> 100% success Before this I had tried the tester with a 230V light bulb. The test created a very distinctive sound and of course it was clear that the light bulb is bad.

The tester consists of a repurposed foto flash. The charging unit is reused. I replaced the tube with a thyristor that can deal with 1200A transients. After minor modification to the trigger circuit I now have a circuit tester that reliably tests circuits as bad