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    DIY Kill-A-Watt

    If you want to know how many 100 watt lights are turned on (without caring about actual watts) you could use a part like LM3914. You would need a circuit that rectifies AC to DC and possibly amplifies/divides it so the DC iutput to the LM3914 drives one output per 100 watt lamp.
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    Converting ATX PSU to bench PSU, need to tweak -12v line

    The way I wired it, described in post #2, doesn't have a power switch. It turns on with the PSU.
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    Converting ATX PSU to bench PSU, need to tweak -12v line

    I needed -12 volts @ 2.1 amps for three synchro-to-digital and digital-to-RVDT cards at work (avionics electronics lab stuff you don't see with most other off the shelf PCI cards) so I came up with the DC-DC converter solution. The isolated DC-DC converter allows powering the input with any...
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    Converting ATX PSU to bench PSU, need to tweak -12v line

    No way to do it without very extensive mods to the PSU. But I had a PC at work that needed -12V @ 2 amps for some PCI boards that were installed. I bought a 12 volt 30 watt DC-DC converter with isolated (important) output. I wired the inputs to the PSU +12 volt output, and the + output to PSU...
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    Silk Screening/ custom Decals on aluminum

    If you want it etched ir engraved, check with the school machine shop. If silkscreen printed, does the school have an art department or one that does signs?
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    Power supply switch?

    It works and is safe to do so long as those are the only connections between the two PSUs. As matrix563 posted, adapters are available to avoid cutting into the PSU cables. Or if you are comfortable with doing so, you get to keep $5-$10. A disadvantage of using a toggle switch is you would...
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    Power supply switch?

    One way is to remove the toggle switch on the stereo PSU. Then splice the green wire on the stereo PSU to the green wire from the PC. And splice the black wire on the stereo PSU to a black wire on the PC. The power button on the PC will turn them both on and off.
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    Anti-gone to crap thread ....

    You can use something like a 0.01 ohm shunt. Then amplify the voltage across it if needed using an INA168NA shunt resistor amplifier (a resistor to ground determines the gain).
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    This forum has gone to crap

    There are only so many ways to wire up LEDs, fans and switches that is not covered in previous threads. So we are out of fresh material here.
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    need help understanding how to wire lcd panel

    Have a look at sime LCD panel controller cards here: Here is a connection diagram for one of them to your LCD panel model:
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    need help understanding how to wire lcd panel

    Electrical engineer here. You appear to have a flat panel display that has 6 bit red, green, and blue data inputs and horizontal and vertical sync. I am guessing you want to interface it to a VGA or DVI card in a PC?. Without the hardware and firmware that goes in between, it wont work.
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    How to monitor home power consumption???

    You could use a power monitoring meter such as the ones shown here: I am using the Nexus 1250 f to monitor 115VAC 400Hz power usage for a project at work. But you are looking at $2000 to $4000.:eek:
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    Dust Removal

    Unless the battery is installed and there are electrolytes (such as are found in laundry detergent) in the water. Then galvanic corrosion occurs and the cell phone or iPod is toast.
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    Where to Buy Non-Ferrous Magnet Wire
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    Not enough power from USB ports

    Once I shorted a 5 volt, 120 amp PSU with my wedding ring. Got a nice 3rd degree burn from it.
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    Antec hard drive mount replacement screws?

    Go to and search for "shoulder screws".
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    AC Power Adapter Question

    I didn't get it wrong at all. While the AC frequency for power coming out of the wall is 60Hz, the sound produced by a transformer plugged into it has a fundamental frequency of 120Hz. BTW i'm an electrical engineer too.
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    AC Power Adapter Question

    Another possibility (since it is a high pitched whine) is that the adapter may contain a regulated switching power supply. If that is the case, the whine will be several kilohertz, not 120 hertz. I know some adapters for Linksys ethernet switches contain 3.3VDC supplies.
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    Switch Identification???

    Looking at the four pads for the switch on the back side (your second picture), two pins are bridged together on the left, and two are bridged together on the right. Therefore, the switch functions as a SPST.
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    Dust free case - work trailer environment

    Have a look here: It starts at $2800 USD though.
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    Voltage rating on TRIACs

    Yes, if it will fit. The voltage rating refers to the maximum voltage that can be applied to it and still operate within it's other specifications.
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    Wiring Clean Up

    Many people hide wires behind the MOBO tray; except that doesn't work if your MOBO tray is not removable and the right side cover is not removable either. Also, if your PSU is at the bottom of the case (think ANTEC 900), that is a special problem. Figure out in advance how many of the power...
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    Quality Fan Controller?

    I have a Vantec NXP-305. But it also has annoying LED lights that I cut out. :mad: I guess BLING is more important to manufacturers these days than making a product that simply works?
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    Resistors for LED

    My older sister and brother-in-law use to own a Radio Shack store. Here's their qualifications: Him = former department store credit manager Her = RN (registered nurse)
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    Resistors for LED

    I can't say what resistor without knowing the voltage source. But you can calculate it: Resistor = (sourcevoltage - 3.4)/.020. The result is in ohms. Choose the closest resistor value that is equal or higher. For example, if your source is 5V: (5-3.4)/.020 = 80. So 82 ohms is close. If...
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    24V from a PSU?

    Can we back this thread up to about post #14? :confused:
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    24V from a PSU?

    I have tried it... you get sparks. :D The DC-DC converter idea works though. I used a few when I needed -12V at 2.5 amps for some computers at work.
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    24V from a PSU?

    You mean two 12V molex from a standard ATX power supply? The problem would be connecting yellow on one to black on the other, thus shorting out the power supply.
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    24V from a PSU? and are good sources for DC-DC converters. You'll want one that has an input voltage range that your PC can supply (typically rated 9V-18V), and has an output current rating suitable for what you are going to power (it's best to have some headroom... it you need 1 amp, buy...
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    Cable Management

    Doing the wiring right requires at least 14 hours and a 12 pack of beer. :D
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    24V from a PSU?

    Another option which I have sucessfully used is a 12V DC-DC converter with an isolated output, powered from PSU 12VDC. If you need 24VDC (referenced to ground) connect the negative voltage output to your PSU +12VDC, and your load between PSU ground and the DC-DC converter positive output.
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    24V from a PSU?

    There is 24 VDC between the blue (-12V) and yellow (+12V) PSU wires. Your circuit cannot rely on the 24VDC being referenced to Ground however, and is only good for 0.5 amps maximum.
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    ESD: Truths, myths, and flat out lies

    Mods should rename this thread "ESD: Truths, myths, flat out lies, and bullsh*t". If I were a person looking for accurate information regarding ESD I would become completely confused by the variety here.
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    I need a modem that doesn't die after 4 months

    You may have a heat problem if the modem is sitting on top of a PC, or modem and a router are stacked.
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    how many switches can i have stacked?

    LAN connections between computers would probably have no problems (but I don't know what your network traffic looks like). But if too many tried to use the WAN connection to access the internet at once then you could have problems.
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    how many switches can i have stacked?

    Depends on what you need to do. You could connect 16 more switches and have a total of 256 ports. But if your WAN connection to the first switch is to a 1Mbps DSL modem you are going to have quality of service issues.
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    Ethernet Switch Recommendation?

    I'll take a look at HP Procurves. I already tried the Cisco website and went away more confused than when I started.
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    Ethernet Switch Recommendation?

    I am designing a test system that has three 8-bit ethernet microcontrollers connected through FPGAs to some non-standard serial buses transmitting and receiving 16-bit serial data at 1Mbps clock, at some data rate (maybe up to 500 messages/sec...
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    Lcd, wiring help please

    What is it? A manufacturer and model number would help.
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    ESD: Truths, myths, and flat out lies

    Policy where I work is not to wear ESD protection when working on anything that is powered. Most of our equipment is 28VDC and 115VAC 400Hz. And believe it or not kids, 28VDC bites if you touch it and are well enough grounded.