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    Transistor radio repair - Philips RR-230

    You cannot measure impedance with a normal everyday multimeter. Only indication, if moving coil type meter, is a click from the speaker and some resemblence of a circuit in the speaker coil. Getting good sound from the earpiece just means you are listening to the un-amplified audio. Fault still...
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    Help required on Logitech Z-2300 toroidal transformer #2

    As quoted earlier, I think you need to supply the complete diagram. As it stands, if your original unit was a split supply, your #2 diagram will feed reverse polarity voltage to the normally split negative supply. Shown attached is a standard arrangement from a transformer rectifier.
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    Transistor radio repair - Philips RR-230

    My opinion also....:)
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    What can cause a DC relay to click on and off continuously?

    Bad earth connections in automotive are a fairly common problem and can lead to all sorts of feedback problems. It is almost impossible to say just which bad earth could end in your present situation but it certainly sounds like it. The every few seconds sounds like it running back through an...
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    Transistor radio repair - Philips RR-230

    Distortion there seems almost over the entire range....some of the crackling and popping might be from a scratchy volume control pot.
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    Transistor radio repair - Philips RR-230

    It's a thing called experience and usually gained over many years. Today's radios tend to be a 1 chip affair. For the output, start at the centre pin on the volume control and work towards the speaker . If you Google old transistor radio schematics you will end up with heaps of examples. Most...
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    Where to find a rectifier that meets these requirments?

    That is some serious power levels and I suggest probably not a conventional approach. Can you supply more details on the overall application.?
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    Help required on Logitech Z-2300 toroidal transformer #2

    Where does the transformer come in...?? Transformers work on ac, not dc. I suspect you are talking about converters, not transformers so show your complete diagram.
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    I cant measure voltage on 100 picofarad capacitors on multimeter

    Show the circuit.
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    Help with capacitor question.

    Yes...but your pic does not show voltage.
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    Is this VFD compatible with this AC motor?

    Cannot get to your link for the controller BUT........ Normally vfd's run 3 phase motors....... Your motor is a split phase single phase motor Your comments refer to the controller running ac/dc series motors which the above is not. Series mootors are brush type motors as in hand drills, vacuum...
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    Need help with DC Dimming seven seg displays.

    The clock pulse usually handles the time on of each segment driver transistor.
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    Fixing vintage Radio/Record player for mother and need help with the fuse.

    And you have output..??
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    Fixing vintage Radio/Record player for mother and need help with the fuse.

    Start at the power cord. Check you have both conductor continuity from the wall plug to the terminations in the unit terminal strip. Check continuity through the on off switch to the transformer primary. Check primary winding for a circuit, could be 40r more or less depending on many things...
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    Fixing vintage Radio/Record player for mother and need help with the fuse.

    As previously stated, show the circuit diagram so we can follow and advise. Otherwise it is akin to getting directions from point A to point B without a copy of your area's roadmap. Even more difficult to try to explain to you where to look with your limited knowledge on a common gear basis. You...
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    Need Help with simple 9V circuit design.

    Hope you threw out that "smoking" regulator.
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    Fixing vintage Radio/Record player for mother and need help with the fuse.

    Look wire wound...did you measure the resistance of the shown device..?? Show the schematics.
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    Buzzing in viewsonic VA2407h LED monitor

    Just be careful poking around in the power supply section as there is some high voltage dc (300v+) Good caps in there can hold a decent wack for quite some time after power down. I tend to approach any (powered down) caps , especially the larger ones, with a 1K5 5w resistor with a couple of...
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    Watt Minutes Meter for Small Electronics

    min reading 10wh...each pulse min 2.5wh........
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    Direction of Current in AC circuits.

    It's no wonder you have trouble understanding as it seems you do not follow the answers. Harald described it quite clearly in the first sentence of his reply #2.
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