Is there possibly DC on the mains at the studio?
It happens in some areas.
This could cause issues with your transformer.
It happens in some areas.
This could cause issues with your transformer.
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No other amp react this way at the studio so I don't think so.
But I can check if you want.
Do I plug a multimeter straight into the power wallet?!
actually that could explain some tiny details we encountered when we build the thing up.
how can i be sure i don't have DC on the mains ?
how can i be sure i don't have DC on the mains ?
Mains DC and Transformers
" It can also be measured, but to do so requires that one works on live components. This is not recommended as it is inherently dangerous.
However, if you must (and PLEASE take extreme care), you need a 100k resistor and a 10µF non-polarised capacitor, wired in series. Connect this circuit across the mains (power off!), and connect a DC voltmeter across the capacitor. This attenuates the AC enough to prevent the front-end of the meter from being overloaded, and the DC voltage is easy to measure. Expect to see the DC vary around the zero voltage, with a normal variation of ±25mV or so (typical - residential areas). The alternative method is to measure the DC across the diode/capacitor network in the circuit of Figure 3. Do not connect or disconnect the meter with the circuit live, and use alligator clip leads to make the connections." Rod Elliott
Worth reading everything before proceeding.
" It can also be measured, but to do so requires that one works on live components. This is not recommended as it is inherently dangerous.
However, if you must (and PLEASE take extreme care), you need a 100k resistor and a 10µF non-polarised capacitor, wired in series. Connect this circuit across the mains (power off!), and connect a DC voltmeter across the capacitor. This attenuates the AC enough to prevent the front-end of the meter from being overloaded, and the DC voltage is easy to measure. Expect to see the DC vary around the zero voltage, with a normal variation of ±25mV or so (typical - residential areas). The alternative method is to measure the DC across the diode/capacitor network in the circuit of Figure 3. Do not connect or disconnect the meter with the circuit live, and use alligator clip leads to make the connections." Rod Elliott
Worth reading everything before proceeding.
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ahah I read it all but will do it again at least one other time as english insn't my mother language.
For now the sentence "This is not recommended as it is inherently dangerous" kinda heavily blinks to my eyes ahahah.
i'll pick up a DC Blocker at an electronic store and have a try with the amp,
i suppose i'm more confident with a professionally made hypothetical solution than with a hazardous test made by myself on the main AC !
i'll try to do it today and will report the result.
For now the sentence "This is not recommended as it is inherently dangerous" kinda heavily blinks to my eyes ahahah.
i'll pick up a DC Blocker at an electronic store and have a try with the amp,
i suppose i'm more confident with a professionally made hypothetical solution than with a hazardous test made by myself on the main AC !
i'll try to do it today and will report the result.