DIY filter chokes

So, I have been experimenting with filter chokes for tube preamp power supply and it really makes lots difference! I like it much better than my transistor regulated power supplies and the classic unregulated RC filters.

So, I´m thinking about DIYing my own filter chokes.

I know how to calculate the needed inductance and maximum DC resistance, and making good power supply out of existing chokes.

What I can´t find is info on how to calculate the proper number of turns needed for a given Henries value versus the DC current running throught the chokes.

I mean, a 8H 100mA choke is one thing, and a 8H 200mA choke should be another thing, with more turns or more core.

Also, should the core be gapped or there is no need for his?

Any liks where I can read about this stuff is very welcome. I can´t find what I´m looking for at the websearches.

I recall that Radiotron 4 has a lot of information on that topic. You've been around here often enough that I'm sure you've already downloaded a copy :grin:

Qualtek makes what they call an "RFI" filter which is an IEC inlet package with caps and parallel inductors for $10.

Yeah, I have a copy. I just opened it for a reading but, as I expected, there was no info on WINDING CHOKES. But good power supply/filtering info, but it´s definetly not what I´m looking for... :sad:

Chokes are so cheap, by the time you got finished winding one, processing it, doing the mechanical, it would probably cost you more than an off the shelf model.Plus, with power supply chokes, you have to be careful about arcing. The ones for sale have usually been hy-potted to many thousands of volts to make sure they don't arc out.

Now para-feed chokes, there's where you could save some money.

I´m talking about Power-supplu chokes. It´s not that I don´t intend winding parafeed chockes one day, but I´m sure it´s much more complex...

Now arcing sounds like danger to me... I think I´ll just buiy some chokes and forget about winding my own.

i tought that in chapter 4 (or was it 5) there was much info about core's en inductors. i can be wrong.

Hi Rafa

This is something that I want to check out as well. I much prefer choke supplies on guitar amps above other types. I really want to hear how they work on a good mic pre.

Hammond have a wide selection, go to

http://www.tubesandmore.com

& search for "choke".

Peter

I have a big ol Thoradarson choke that I can hack if you guy's want to see it.

It probably would not be more than just a bunch of wire wrapped around some barn roof lams, but WTF!

...that I can hack if you guy's want to see it

Click to expand...

Of course we want to see it! What kind of question is that?

/Anders

OK then. One person egging me on is all it takes to get me hackin! :razz:
I will put it over in the Lab.
cj