AC Mains Filter

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220V is safe and so is, even, the British 240V. I used to check whether there is a power in European and UK mains by touching the wires with the back of the palm ( so the muscles do not contract and keep holding the wires indefinitely ). I, just, got a tickle and nothing else.

I'm scared.............this is non compos mentis.....
 
C'mon, gentle folks, this is diyAudio, so get your hands dirty, or go fishing!
There's a lot of valuable info in the file, even though I personally prefer a more global approach, including the trafo and other parameters, and looking also into the time domain.
All commercial AC filters, including Schaffner, ring like bells when hit with a pulse.
 
C'mon, gentle folks, this is diyAudio, so get your hands dirty, or go fishing!
There's a lot of valuable info in the file, even though I personally prefer a more global approach, including the trafo and other parameters, and looking also into the time domain.
All commercial AC filters, including Schaffner, ring like bells when hit with a pulse.
Interesting - any results available online? (I use them and any learning analysis would be interesting)
 
C'mon, gentle folks, this is diyAudio, so get your hands dirty, or go fishing!
There's a lot of valuable info in the file,
There's no reason for anyone to make their own AC Mains filter, just use a filter from schaffner or use a power entry module with a filter from schurter.
The document from the op is mostly nonsense, quite frankly just dangerous and in some countries would constitute non-compliance in respect of the applicable electrical safety regulations.

You won't be able to enjoy your DIY audio project if you are deceased.
 
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There's no reason for anyone to make their own AC Mains filter, just use a filter from schaffner or use a power entry module with a filter from schurter.
The document from the op is mostly nonsense, quite frankly just dangerous and in some countries would constitute non-compliance in respect of the applicable electrical safety regulations.

You won't be able to enjoy your DIY audio project if you are deceased.

I have two schaffner modules FN9262-6-06 and FN394E-6-05-11. The 9262 did a reasonable job of reducing (not eliminating noise) based on selecting that particular model via the noise in my house electrics. The 394E in the same environment does a better job - however this showed my bridge rectifiers were ringing with the toroidals. With a variable snubber that was cancelled out on the secondary side using a scope. There may be more noise but for now that will do as the amp is a hybrid tube/SS headphone amp with other issues that need addressing in the design.
 
The 9262 did a reasonable job of reducing (not eliminating noise) based on selecting that particular model via the noise in my house electrics. The 394E in the same environment does a better job
It certainly helps to know the frequency and amplitude of the noise so you can select the appropriate filter attenuation curves. I would imagine most hobbists / DIYer's wouldn't have any ability to undertake measurements or in some cases they would be unable to determine whether its mains noise upstream or an earth loop (mains hum) because the way their equipment is connected, so its more or less any filter is better than no filter.
 
I have two schaffner modules FN9262-6-06 and FN394E-6-05-11. The 9262 did a reasonable job of reducing (not eliminating noise) based on selecting that particular model via the noise in my house electrics. The 394E in the same environment does a better job - however this showed my bridge rectifiers were ringing with the toroidals. With a variable snubber that was cancelled out on the secondary side using a scope. There may be more noise but for now that will do as the amp is a hybrid tube/SS headphone amp with other issues that need addressing in the design.
6A at the primary side seems an overkill. I use 2.5A type for my class A amp with a constant total power draw of 200W; the attenuation graph looks better vs the 6A type. The primary current does not go above 1 A... plus, there's the NTC in series with the primary, so the surge current is not an issue, either. Do you really need a 6A nominal current type?
 
6A at the primary side seems an overkill. I use 2.5A type for my class A amp with a constant total power draw of 200W; the attenuation graph looks better vs the 6A type. The primary current does not go above 1 A... plus, there's the NTC in series with the primary, so the surge current is not an issue, either. Do you really need a 6A nominal current type?

The smaller was retrofitted to an existing solid state class AB amp with stong class A bias amp fused at 6.3A. Not a brilliant 1990s design and cramped case.

The larger is the single inlet for three troidals (will be 5 or 6 later) in parallel totalling 520-600VA. So the oversize is me being cautious. Later a custom tramsformer is likely reduce the requirements. I should say the current transformers are used as a project bench supply hence the oversize.
 
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