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  1. S

    Halloween Project Help!

    I don't know if you're in the states. Unless you're seriously wanting to 'do-it-yourself' with this, I'd check the local five & dime store and see what the chinese came-up with this year. Last year they had a bunch of small electronic skulls with the 'electrifying' effect you're talking...
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    Buying stuff from China.

    Nope. Original manufacturer markers are made NOT to rub-off, that's why counterfieters usually just paint over them. Look at the bright side, if you rub the covering off, you'll see who actually made the chips, underneath the paint. (unfunny humor). ps. wdancer has a point.
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    please help

    Good advice from duke37. With a new motor, your problem is more likely a current issue, than a voltage one.
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    My $4 precision weights

    I worked on atomic apsorbtion spectrometers and gas chromoatographs in a pervious job. We had an old Ukranian chemist there, who was telling me he was now required to measure pesticides in parts per billion. I was standing there, impressed with the technical aspects of equipment capable of...
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    Crystal Identification!!!!

    I also think it's a resonator, but I'd email that picture to MuRata, and ask them.
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    hot plate quit- no power

    COULD be a break in the wire, but I still think you're missing the most probable cause, a thermal fuse. Is there asphestos-type covering over one of the ends of the connection to the actual nichrome heating element wire? Maybe you could pull back any insulating covering, and find the...
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    please help

    Do you have a drag on the rotation? Is this an old used motor, with possible bad bearings? Is the motor getting unusually hot during operation?
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    Buying stuff from China.

    I can't see the markings on the IC's, but they could well be genuine, though I would guess they were salvaged from scraped equipment. China buys a lot of scrap gear and pulls anything they think they can re-sell. Don't get me wrong, that's not all they do. We've got an electronics salvage...
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    My $4 precision weights

    .0001mg per NIST. Temperature doesn't affect weight by itself, but it's probably a factor in some formula involving barometric pressure. I don't know, because we have to keep our dimensional lab at a constant 68 degree F. So we don't deal with it. You still got a pretty good deal for the...
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    hot plate quit- no power

    Like *steve* said, can't see your picture very well (too small). Having repaired a lot of hot plates, I'll offer this: Wires don't go bad, but they break, or break mostly at the electrical connections. Check the ends of the wires to make sure they're connected. (or for breaks in the wire)...
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    Design your own headphones

    I think we have those in the States already. They're called low-riders, with boom-boxes in them. They rattle my skull pretty good, just pulling-up next to one at a stop-light.
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    HP 8903A Audio Analyzer schematic

    I don't have the schematic for your board. The HP8903A originally had 2 relays on the A6 board, after all the mods, when they re-designated the unit the HP8903B, it had four relays on the A6 board. There have been so many modifications on this unit between models, I don't know half of what...
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    HP 8903A Audio Analyzer schematic

    Not going to be able to help you with this. My schematic has only 2 relays, with a dozen 'PO Service Sheets', that specifically reference modification to the A6 board. Not a one of them discusses the addition of your 3rd relay. I think you've got one of those 'stop-gap' middle of the...
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    My $4 precision weights

    Sounds like a good $4 deal there (not to mention your $15 scale). We measure in the 10ths of a mg. We have to watch barometric pressure, wind- currents in the room, fingerprints/dust. Our set-up costs a little more than your $19 (total) set up. Good buy!
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    Design your own headphones

    You've got two votes, good luck.
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    tv repair help please

    I don't know your set, or solution to obtaining an original remote, but it sounds like what you're talking about is a 'convergence' issue. Just trying to add info, so people here have a better idea what you're talking about.
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    HP 8903A Audio Analyzer schematic

    The manual I have is for prefix 1942A - 2514A, but we're talking hundreds of pages, and I only have the print copy. (So I can't just 'send it to you'). I'll check it for your 3-relay A6 board, and see if it's on my schematic. I assume you already Googled it, to see if you can get a...
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    Trying to read a cement power resistor

    Don't know either, but I know about how most other manufacturers mark their big resistors. Your wattage and/or mfgr series is probably their '40B' designation. But you'll have to find something on the web that identifies that number to the manufacturer. I'd also wonder if your 1.5 OHM K...
  19. S

    multimeter help

    I'm not familiar with your model, but if you heard a 'pop', you've probably got some physical damage. If you're sure you didn't blow the fuse, take the circuit board out and look carefully at the component side for damaged components.
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    Solution by Explanation

    *steve*, your problem is you know how to solve problems right away. The rest of us are the ones who have to deal with the 'AH-HA!' moments, which come much later.
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