First Lm3886

[AndrewT]

Originally posted by Ted205
PSU filter will only reduce RF entering and leaving the power supply from the mains. These are not necessary.

Originally posted by Ted205


For diy you can I live without them.

I believe you are wrong.

That is why I always advise that any and every buffer and amplifier has an RF filter on the input. Without exception.

[akis]

Using my guitar amp's schematic as an example, there are "filters" that curtail high frequencies in many places, almost all feedback loops on every op-amp stage. Is that what you meant or did you mean power line local bypass small capacitors (100uF) positioned close to the op-amp chips?

[Ted205]

Originally posted by AndrewT



I believe you are wrong.

That is why I always advise that any and every buffer and amplifier has an RF filter on the input. Without exception.

i'm referring to power line IEC socket filters.

I agree they are a good idea. I personally use them but they are not strictly needed if you're not concerned with EMI & RFI, for example when building your first simple amp

[Juergen Knoop]

Originally posted by AndrewT



I believe you are wrong.

That is why I always advise that any and every buffer and amplifier has an RF filter on the input. Without exception.

I believe there is a misunderstanding. If the amp circuit itself is build properly with all the rf precautions, then a IEC inlet filter makes imho only a little difference.
AND if the amp circuit is not done properly, the IEC inlet filter won't help very much.
Anyway...I use them, if I have them lying around and if I don't have any, I can live without.
regards

[infinia]

Using toroids in the power circuit trades a little DC regulation for little to no mains RF isolation. A better choice is to use a little overrated EI core with a split bobbin. Failing that, then even bigger RFI input filtering is needed and your probably never going to approach the effectiveness of a proper transformer. Twisting wire in cables and proper grounding techniques helps but once RF is inside yor box it's much harder to get rid of.

[PJPro]

Originally posted by Stuey
PJ, assorted IEC sockets are sold by practically every supplier of electronics gear. Over here, even the crappiest store has a range of a few types.

Do you have any electronics suppliers locally - even basic ones? They're worth using for this sort of hardware, if not the more esoteric stuff.

Stuey

My emergency store is Maplins (within about 10 miles of me). However, these Schurter modules are a little more tricky to source. Even Farnell (who do not usually charge postage) want £15 to deliver these as they are not stocked in the UK.

However, I haven't checked all the suppliers on the list behind pacificblue's link. But I did check every result returned by Google on the part number.

[akis]

I biought this from Farnell and never gave it a thought. I also had some older ones from disused/broken PC PSUs, almost exactly the same, come complete with capacitor across L/N already soldered on as a bonus.

http://uk.farnell.com/jsp/search/pro...sp?SKU=1516058

3 pounds 29 pence

Am I missing something else?

[AndrewT]

pro wants a filter combined with IEC inlet and fuse and switch.

[PJPro]

I've possibly got carried away with the power inlet modules. That said, they look/feel extremely well made, they come with nice aluminium shielding and the internal components appear to be potted.

[PJPro]

Talking about getting carried away, I've been looking at the hookup wire over on Hifi Collective. Gulp. It's not cheap!

I was intending to use my trusty store of Maplin's finest. Will I hear benefits going for something a little more expensive eg the gold plated copper used by Peter Daniel?