EMI Filter/Line Filter

Fox Mulder

The Truth Is Out There
Jan 22, 2009
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Dhaka, Bangladesh
Guys,
I need help understanding this schematic.

I'm guessing the middle section (with a black bold line and 6 boobs) has 2 transformers? Or 1? Why does it say T1 Isolation on top? OR is it a T1 ISOLATION DS2290 IC?:hypno:

Also, what is S1 Voltage on the left?

I can only identify the 100k Resistors on the right :P And of course, the input and output, haha.

Btw, is this even a valid schematic? :lol:

Edit- Sorry, here's the schematic:

untitled.jpg
 
I am completely green in this area, but that S1 looks to me like some kind of a (S)witch.

Also i understand that the discontinuous line connecting 2 switches makes them work only in parallel and never just one of them.
 
S1 is a switch allowing you to switch between two input voltages to the transformer.
My guess is that it would allow switching between 120Vac and 240Vac, but that' just a best guess.

That's a single transformer in the middle with multiple windings.

The 100k resistors would generally be there to ensure to balance the transformer output for minimising hum.
It impossible to wind a perfectly balanced, centre tapped x former, the resistors make a faux centre tap, in this case referenced to earth.

It say isolation because that's what it's doing, the live and neutral of the incoming mains are completely isolated from the output voltage of the transformer.
The only common point is earth/ground which is standard.

Hope that helps.
 
S1 is a switch allowing you to switch between two input voltages to the transformer.
My guess is that it would allow switching between 120Vac and 240Vac, but that' just a best guess.

That's a single transformer in the middle with multiple windings.

The 100k resistors would generally be there to ensure to balance the transformer output for minimising hum.
It impossible to wind a perfectly balanced, centre tapped x former, the resistors make a faux centre tap, in this case referenced to earth.

It say isolation because that's what it's doing, the live and neutral of the incoming mains are completely isolated from the output voltage of the transformer.
The only common point is earth/ground which is standard.

Hope that helps.

You're right actually. I recall the 'product' mentioning it was universally operable or something like that.

That transformer is a dual primary/dual secondary transformer, hence why it's that way.

S1 I'm guessing is to select between 120/240? Not sure though as the transformer specs aren't listed.

You are better off going with something like these-
http://mysite.verizon.net/vze22yzp/id3.html
http://links.dalrun.com/Electronics/Docs/Surge_Protection/files/AC Filter & Surge Suppresor.htm
http://www.hifi-forum.de/viewthread-168-11.html


Thanks for the links brother. I'd like to know what's wrong with this.
I recall now that the S1 is the voltage selector.
 
Nothing really wrong with it, but it's simply isolation. No real filtering going on and no protection.

A mixture of the Jon Risch design, with a transformer, can be done for a decent price and would slay any Monster/Furman/Etc on the market. This would give you isolation, protection, filtering, balancing, etc.
 
Nothing really wrong with it, but it's simply isolation. No real filtering going on and no protection.

A mixture of the Jon Risch design, with a transformer, can be done for a decent price and would slay any Monster/Furman/Etc on the market. This would give you isolation, protection, filtering, balancing, etc.

I'm confused as to which one to choose.

Do I build this: http://mysite.verizon.net/vze22yzp/id11.html
And then this: http://mysite.verizon.net/vze22yzp/id22.html

And chain them up? I'm sorry, it's all going over my head because the first link doesn't have a transformer(?). Or am I mistakening a transformer for an inductor in the first link? :p

--------------------------
Edit: Or do I save up some cash and get a chinese made Apollo Online UPS in order to get a Pure Sine Wave? 2kv costs around $600 or so.

I'm a n00b when it comes to EEE. And where I come from (Bangladesh) - people who are good at EEE leave the country. I don't know of anyone who can figure out the specs of a transformer needed for the Jon Risch design. Could you kindly tell me the specs? It's 220v/50hz here, btw.

Thank you.
 
Sorry for bumping this up guys. I'm completely overwhelmed and frustrated. My recordings suck because of how fuckin dirty my electricity is. (I live near an industrial area). I can't afford an online UPS, nor a market-grade Power Conditioner. Feels like OCD, lol.

If someone could help me out a bit more...
 
Nothing really wrong with it, but it's simply isolation. No real filtering going on and no protection.

A mixture of the Jon Risch design, with a transformer, can be done for a decent price and would slay any Monster/Furman/Etc on the market. This would give you isolation, protection, filtering, balancing, etc.

I'm sorry, but I can't properly interpret this.
Do you mean to say:

1. Chain up Risch's Power Filter with his Digital AC Filter, which has got transformers in it and is very easy to make?

2. Or just install a transformer into his Power Line/Surge Protection filter? If yes, what variables should I be aware of?
 
well, this is a double transformer and the 6 boobs at the left sides are two switches with double pole single thorough switches. and this is a valid diagram for emi filter.