Electronics question

[TriplexDread]

OK no real catagory for this to go into so placed it here

Sorry thought I'd ask here first before I get off my bum and indulge in gormless hours of research

Question:

I need to replace a toroidal Ferrite coil Choke in a AC/DC laptop PSU
Does anyone here know the calculations to work out the type of replacement needed for a 19v @ 4.7A (90watt) or how many winds and guage or enamelled cable are needed....

I'm not sure of tolerance probs standard 5 - 10% before overload or damage

 

[bodhi]

Think this is a tumbleweed moment TriplexDread!!

 

[TriplexDread]

Ahhh

OK looks like gormless research then

 

[floppybootstomp]

I have not a clue.

In all my years of fixing stuff I've never wound a choke or a transformer, although I've known peeps to make their own custom mains transformers before.

There are formulas available for TX's but I've never come across any for a choke.

Can you not just buy a replacement?

 

[TriplexDread]

I might be able too but i cant really find one that has the same configuration as this. Its a twin wound one with 0.9 enamelled wire. All i can find it single wound

It needs to be wound for both ground and phase outputs on the same ferrite coil

I was wondering if two separate resister style chokes would do the same but then again I dont know the 'Henry' value to work out which ones I need