OT: killed my computer

I believe that even Suns of the SPARCstation-5 period used the ATX standard as far as the power connector went. The form factor of the power supply would not fit any PC of the period, but you could set an ATX supply beside the computer box with the lid open and connect an ATX power supply to the system board to run things in an emergency. (I've never actually tested this, so I may be wrong here.)

Much later the same connector is used for the voltage sense feedback in the Sun Blade 2000 -- and probably the same pinout too -- but there is a much larger connector with really serious sized wires to actually *power* the board.

BTW If you ever get a chance to open up a power supply for a Sun Blade 1000 or 2000, do so. It has to be the most beautifully constructed power supply of any that I have ever seen.

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But -- before the ATX came along -- with the IBM AT computers, there was one thing which was not done right in the power supply. The other voltages (12V and others) were dependent on the 5V being loaded to a certain percentage of max before you got regulation on the others. As a result, if you had an AT with only one hard drive, you needed to run a big load resistor on the +5V pins of the second drive's power connector (and the resistor was mounted where the drive would mount, so when you added the second drive, the resistor would be removed.)

Sounds like a good design -- which may be why Sun started using it in the SS-5 and similar machines.

Well ... not *any* power supply. But well designed ones, including lab bench supplies, yes. The nicer ones even offered adjustable current limit, so it could be used as a constant current supply within the voltage swing range of the supply.

Enjoy, DoN.

Reply to
DoN. Nichols
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On Wed, 3 Dec 2008 10:10:54 -0500, the infamous "Buerste" scrawled the following:

So your power supplies "keep it up" while power switches 'n glitches happen, and filter out surges and noise?

Good, but methinks thou art on borrowed time.

-- Smell is a potent wizard that transports you across thousands of miles and all the years you have lived. -- Helen Keller

Reply to
Larry Jaques

I don't much believe in UPS's either. The power is quite good here and I'm much more likely to lose data from a program crash than from a power failure. The power supplies I've seen fail were chiefly from fan failure followed by overheating and self-destruction. Decent power supplies have crowbar protection which keeps the machine itself from being damaged under most circumstances.

And, of course, laptops/notebooks/netbooks effectively have a built-in UPS.

But if I lived in some place like central Florida, I'd probably have UPS's (as well as good supplies).

Best regards, Spehro Pefhany

Reply to
Spehro Pefhany

I didn't write that, but I am quite familiar with 'Q' (Quality). I was a radio & TV broadcast engineer, I've built custom telemetry receivers for NASA, NOAA, the ESA the ISS and the aerospace industry. Electrolytic capacitors have a limited life span, generally 2000 hours at the rated temperatures.

I built a seven stage filter to remove a single channel from the CATV feed at a school. The 'Q' was high enough that the 1 mV RF input would give a nasty shock. It was built in a Bud diecast aluminum box with an internal shield made of sheet brass to divide it into separate compartments. I built it with torroids & glass piston capacitors for the series tuned stages, and tuned core inductors with polystyrene capacitors for the parallel tuned stages. It was used to replace a scrambled CATV channel with the school's local ETV feed.

Reply to
Michael A. Terrell

Data loss due to power outage is only the tiny tip of the iceberg.

Reply to
clare

'Borrowed time' based upon what technical knowledge? When does a power supply see some of the 'harshest' electricity? When a computer grade UPS is in battery backup mode. For example, this 120 VAC UPS outputs clean AC mains electricity. But when in battery backup mode, that modified sine wave is two 200 volt square waves with a spike of up to 270 volts between those square waves. Harsh? Those are numbers required before doing any 'methinking'.

Where is this 'clean' electricity when using a UPS? Exists mostly in myths when one knows without first learning facts - especially without learning numbers.

If 'dirty' electricity puts a supply on borrowed time, then a UPS in battery backup mode is also a threat.

Anything that a UPS does to protect a power supply, instead, is designed into any minimally acceptable power supply. A solution that costs significantly less money.

Supplies must contain functions that make AC line anomalies irrelevant to computer electronics. Any protection that a UPS might accomplish must already be included in a computer's supply. Anything that might harm that computer's supply would also harm a UPS's supply.

Reply to
westom1

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