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  1. S

    TEK 2467B auto setup repair

    Looks like it's nighttime for you, when I'm awake, so this may take a few posts. First, do you have the service manual, or just an operator's manual? Before you go tearing the scope apart looking for malfunctions, you REALLY should go through the service manual Performance Check (Section 4)...
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    Good multimeter

    I don't know your application, but if you're serious about quality, look at the Fluke meters. They support their meters with a wide variety of optional add-ons, (like clamps). I'd avoid the fly-by-night manufacturers from unknown companies. The Fluke line typically separates their capacitance...
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    Cause of blown fuse.

    Trivia, I've gotten a lot of nice equipment from people who just threw it away when it stopped working. I don't think there are a whole lot of younger people, who even consider the possibility of a fuse blowing, in otherwise undamaged equipment. Excellent point on 'something' causing fuse to...
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    TEK 2467B auto setup repair

    A5 is your Control Board. Two sets of schematics: Serial number B049999 and below, & Serial number B0500000 and above, ... What have you got?
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    TEK 2467B auto setup repair

    I'm looking through the manual now, but it sounds like you're working three different problems right now. First, on the -18V, check your recitifier feeding the LM317, and it's filter caps. Sounds like a cap leakage problem to me. Second, are you sure of your scope probes? Wrong probes, or...
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    3 video card caps blown. Can this be fixed?

    Another possibility to consider, is the wires from the fan. Check the fan wires carefully, to make sure no insulation rub-through, exposing the wire itself to the cap can package. Kinks in the wire, or previous exposure to some heat on the board, could have simply caused an electrical short...
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    mosfet gate drivers? Do they usually fail when transitor fails?

    And to add to what trobbins said, a higher current through the 220 ohm resistor, would just about guarantee the transistor in line with it was subjected to an overcurrent (and would probably be damaged). I'd be looking at that transistor, as well as your gate driver. I can't see the circuit...
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    mosfet gate drivers? Do they usually fail when transitor fails?

    You really need to consider your circuit. Any device failing could cause another device to fail in the circuit. There's no guaranteed, always true, answer. I never assume a single device is the problem (although it frequently is), I always look for what's connected to the failed device, and...
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    Testing of Mosfets. want to be sure.

    Trivia: Be careful what family you're testing with a DMM, it generates it's own voltages and currents when it's testing, and you can easily blow sensitive devices with it. Most manufacturers show a simple test circuit to build for their devices on their data sheets (for each device). Most...
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    125 VAC motor won't start

    And an additional 2 cents to consider: Is the pump ITSELF sticking/seizing? If there's even a slight physical resistance at motor start, the motor won't have the torque to begin spinning the pump. Is it possible your cap is ok, and the pump is seizing? Just something to consider.
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    Weird telephone problem

    I'm late to this party, but have two cents worth. Last time this happened to me, telephone company had automatic test that was trying to determine if the problem was in their gear, or my house (so I got ringing on one phone, even though the line was otherwise 'dead'). Apparently the phone...
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    Remove mini-knobs from dual mini-pots

    Not familiar with the manufacturerer, but I'd be willing to bet the top cap comes off, and there's a screw holding the knob itself to the shaft. I'm with everybody else, ...only one way to find out; Do you feel lucky?
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    SOS HP8116A

    The main amp ckt is Q501 thru Q513, offset voltages compensated for by U501 and U502. Offset current error compensated by the offset current control amp (which detects voltage at virtual ground at inverting input of the HF amp). The voltage compared to ground & the offset current control amp...
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    I'm struggling with a mystery issue.

    You've done everything I would have done (first). Since it's not your caps, I'd be looking for a 'leaking' transistor. (Though I suppose it could be an IC). Your problem is one of the semiconductors 'leaking' when the electronics 'warms-up'. An easy way to find it, is after the few hour...
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    Full Wave Bridge Rectifier (Odd Output Voltage)

    Mitchekj pretty-much gave you the scoop. If you have no load on the transformer, you're going to read higher voltage than when there IS a load. The caps after the transformer are to help smooth out the AC (ripple) from your transformer sine wave, You're confusing the 'effect' of a capacitor...
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    SOS HP8116A

    Error code 41 is Output Amplifier fault. EVERY time I find this fault it's in your Q503 thru Q513 transistors, the ones under the large heatsink assembly bolted to the chassis. They're all either 2N5160 (HP #1853-0312), or 2N3866A (HP #1854-0784). Simple to just check emiiter/collector...
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    1N4004 Diode

    Your 1N4004 was probably in a bridge rectifier configuration. If you have doubts about THAT diode, check the other three making-up the bridge.
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    Videorecorder problem - see pics

    Arfa is probably right, but I'd clean the heads and rollers first.
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    Parts

    www.support.magnavox.com partstore.com pacparts.com
  20. S

    Tektronix 2235 Scope

    On the web I found : Q Service & IML Test showing stock, but have never bought from them.
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