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  1. S

    Vibration in Electrical Components

    If you find a need later, after some miles on the road, you can consider using one of the 'potting' kits, To 'pot' the circuit board, and prevent vibration problems (like they do with a lot of voltage regulator modules these days).
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    Atari Punk Console propblems

    Double check all of your components, recheck all of your connections. Have you got the ground of your circuit to the ground of your output. How critical is the balancing of the 470K pots. Looks like one might be a linear taper, and the other one an audio taper. Even though you 'know' you...
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    I need an old National Semi data sheet

    This sounds like it might have a proprietary part number stamped on it. If you tell us the manufacturer of the circuit your 8-pin can is in, somebody might have an idea. A lot of manufacturers print partial part numbers of their proprietary numbers, and some of us have a little experience in...
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    Current flow switch

    Look into the glass encapsulated reed switches, or hall effect switches. You might have to play with the circuitry to detect current flow in two different directions, but the devices are simple (they work from the magnetic field). And looking them up, might give you some ideas.
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    resistor

    I'm thinking this might help. The current remains the same through a circuit, the entire circuit through that loop. The potential drop is called the voltage drop. Each component in the circuit will have some voltage drop for each component. The total of the combination of all those voltage...
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    DOA Capacitors

    I read an article a year ago, saying the Chinese had a shipment of incorrectly mixed electrolyte, and they didn't find out about it, until they started getting reports of failures in the field. The bulk of the caps made were supposed to go into hand-held devices, and the manufactuer was...
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    shortwave radio propagation help

    Frequencies matter (as well as atmospherics). Generally speaking, at night the layers move further away from the earth, and reflect radio waves further distances back to earth. (Look up 'skip distance' in communications). On a short-wave radio, you'll hear extremely distant stations at...
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    Linear voltage output & displays

    I've been out of industrial electronics for more than a decade. Omega, Newport, Red Lion, half a dozen other places will have the display you need. Your issue is an extremely common need, and manufacturers make the solution. Good Luck
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    cree leds

    Typically yes. You use a resistor to limit the amount of current (amperage) running through the LED, so you don't 'cook' it.
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    Home Cinema active Subwoofer malfunctioning

    SeasonedTech pretty-much told you the way it is. If you're going to try to do this yourself, I'd start with the capacitors. With the power disconnected, short each of the caps between terminals, to make sure they're discharged. Put an ohmmeter across each cap to look for a short or open...
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    Unknown SMD Transformer

    Just picked-up a bag full of small surface mount transformers. 1/4" square, 3 leads on one side, 2 leads on the other. Bag is marked 'TR-T977' (& Not RoHS) Anybody know who the manufacturer is, so I can find a data sheet? Thanks to anybody who knows.
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    looking for parts

    Yeah there are still 1N34's out there. There are probably a lot of good technical explainations of why germaniun is rad hard compared to silicon. Everything I've read simply says germanium is 'intrinsically less succeptible' than silicon to EMP. Google should explain something about it...
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    looking for parts

    I don't know of a replacement for 1N34. NTE makes NTE110MP as a replacement for the 1N34A. Stay out of Radio Shack, and check a regular electronics parts store for TV/Radio repair, and you'll probably be able to find the NTE equivalent. I don't know the cut-off date, germaniums were common in...
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    Questions on identification of used diodes

    If you got these parts from your dad, they may have military markings on them. In any case, you should be able to google the numbers on the diodes (or whatever device) Then you can either get data sheets on the devices, or look for cross reference if you need to. Other devices usually have...
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    Function Generator Chip

    Are you talking about the old Radio Shack chips? AY-5-8116 Dual Baud Rate Generator (#276-1792) AY-3-1350 Melody Synthesizer (#276-1781) SP0256-017 & SPR016-117 Voice Synthesizer (#276-1782) They were made by General Instrument.
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    no dial tone without splitter

    Many times when you contract for an in-office phone system, the contractor wires their OWN telephones into the system, which are not always wired the same as a conventional phone system. I know, cause they did it once to me. It is also possible, being ATT, that when you cancelled their...
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    Tektronix 475A Display problem [Horizontal?]

    It's tough to diagnose these problems without putting your hands on it. Yeah, you've got a horizontal problem. Unless you've got a problem with the 'position' knob for left/right centering of the trace. You've got a blooming problem, either intensity is too high, or focus circuit problem...
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    Cable source.

    Try a computer supply store, or maybe an industrial electrical supply store. We used a lot of multiwire 16 gauge cable for industrial applications in plants I've worked at. Hell, for a 6' length, you might even be able to check with a supply store or even the wire manufacturer itself, and...
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    Texas Instruments Proprietary Part Numbers?

    Ok davenn, thanks. Yeah, I was using these things in the early 1980's, and I don't remember what for. Maybe I'll get lucky here, and run into somebody who's got a better memory than me.
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    modifying a Velleman kit

    I'd google the manufactuerer of the larger 7-Seg LED's. When you've got data on the LED's themselves, you can google for cirucits using them, then you'll find the most commonly used display drivers for them. With the data sheets on the displays, and data sheets on the display driver, you...
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