1. it's the capacitor, isn't it … at least that was for me

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2. It's common, capacitors have lifespans because of their chemical nature. They are usually the first things that start to fail based on age being the factor of failure.
   For example, resistors a simple wound wires, so they nearly never fail unless components before them failed that allowed too much voltage.
   Things like various diodes also usually don't fail because of age.
   Most common age failure is a battery, second is a capacitor.

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3. I'm surprised that you didn't doublecheck your line freq with the other power meter, Julian. Anyway, that was an interesting romp around the power meter. I use a P3 P4400 Kill A Watt over here in 'Murrica and have never had the need to look inside it.

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4. "Only a few watts out"? That sounds pretty damn inaccurate to me. A watt is a significant amount of power at the domestic level.

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5. The meter is also designed for 120V. With 240V, the needed capacitance is half. Of course, there's also a chance that the half-sized capacitor still works on 120V.

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6. Besides a little lower supply to the 5 V regulator, I am pondering if the reference frequency is correct. Voltages are measured in a ratiometric way, so they would still be O.K. But the frequency is counted against some reference clock. You might see if the frequencies of the resonator you mentioned or a crystal I actually would suspect is the culprit. Normally the crystals also have a mode select capacitor or two. Series resonant or parallel resonant?

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7. The excess material on the plastic is called "flash" the process for removing it is called "fettling" which is done by a "fettler" which used to be a trade back in the day, still might be for all I know.

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8. Is your inverter producing 50Hz?

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9. The pulse output is indeed energy. It can be used to power a pulse LED, like on your main meter. Or sometimes it is used to power an opto-isolator.
   That way, an external device can monitor power usage without a direct ("galvanic") connection to the measuring circuit, either by putting a photodiode over the LED, or sensing the "volt-free" opto-isolator output.

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10. No real surprises there – I was calling this as soon as you opened the case and I saw that big X2 cap – This is a VERY common failure of those cheap remote controlled mains sockets too – I've had loads of those come in for repair over the past few years with exactly this same fault. As the capacitor decreases in value over its lifetime, the amount of current it can pass reduces accordingly until it eventually gets to the point where the available current is insufficient to operate the device. This is especially relevant in those remote mains sockets as these need enough current available to drive a relay, so ANY degradation of the capacitor will result in a non-working unit (the most common symptoms with those are either that the device doesn't respond to the remote at all or, more commonly that the LED lights up but the relay fails to operate, or at least fails to latch on due to insufficient current being available to keep the coil energised

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11. 3rd video on capacitors, lady Ada/search, big clive/nokero

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12. Hi Julian, did you measure the old X2 caps capacity?

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13. Check ZD2

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