Anybody used these ferrite cores ?

[Tolik]

Eva , my ears are bigger then yours!

I have very big ears too 😀 😀 😀 😀 😀 😀 😀 😀 😀 😀

started with rod's project 68 (its 68 isnt it? )

I know Rod Eliott site - a lot of very good projects and ideas.
Project 68 - up to 470W sould realy kick ***😀

another my own circuit with uc3825 controller ( i dont remember but i think it was that) it also used ETD59 core for allot of power , i dont really know how much ,i disassembeled it because i want to use the core for 1kw or so home amp .

Are you got UC 3825 and the core in Israel , or ordered from overseas ? I searched a lot of time for SMPS stuff here but found some chips and mosfets only...

Eva,
I saw your class D project - it`s was realy big peace of enjoyment to compleate it. 😀 I agree with you about class D amps. But for AB or especially for current hangry A classes I`m not sure...
Your explanetions about switching speed are very intresting... Redusing these speeds will increase heat dissipation on mosfets, but from other side, it`s can reduse or eliminate such parasitic effect like dial (rigning) on wave`s edeges... Will see when I`ll start my project.

 

[sss]

Are you got UC 3825 and the core in Israel , or ordered from overseas ? I searched a lot of time for SMPS stuff here but found some chips and mosfets only...

i ordered it overseas.
TI got a supplier in israel , but they wont sell u one chip only , u need to order more then 100
anyway , u can get the same results with sg3525 whitch u can get here.
ferrite cores u can get from junk yards or some old pc power supplies.but if you're making something serious u can order one from overseas.

 

[Tolik]

TI got a supplier in israel , but they wont sell u one chip only , u need to order more then 100

Are you about Rapac ?
Once I tried to order some TDA chip from these guys - they answered that minimal quantity is a box of several hundreds...
There is 2 good suppliers that I know - Farnell in One , & RS Israel.
Both with headquarters in England. Just one bad with these companies- expencive shipping. So I preffer Ebay or small European online shops.

Here is some additionas supplyers of ferrite stuff:

http://www.eastern-components.com/manufacturers/epcos.htm
www.digikey.com
http://www.adamsmagnetic.com/cores.php
http://www.surplussales.com/Inductors/Inductors.html
http://www.arrownac.com/

 

[N-Channel]

Hi,
We normally use E-shaped cores.
Toroids are difficult to wind. And would only be useful for small power smps. The bars are mostly used for antenna.
Have a look on EPCOS website. There is another manufacturer, but I am having a brain freeze.
Cheers.

I love to wind toroids. Especially the smaller ones, they're harder to do! 😉 Seriously though, Although they are a little harder to wind than and E-E, E-I, or pot cores, their superior performance, IMHO, is worth it. I have done toroids for up to several hundred watts, mostly 12V DC-DC push-pulls, but a couple of off-liners, too. FT-140-77 at 50kHz is good for about 300W, and that may be pushing it. For more power in a tight space, I stack two FT-140-77s to be good for about 400W at 50kHz. Biggest toroid I wound was an Amidon FT-240-77, for about 500W, much less than the '240 can handle at 50kHz. If I can find some pics, I will post them. Until then, here are a few powdered-iron toroid-based SMPSs I have done over the years.

 

[Tolik]

Very intraestng projects, and nice PCB`s Steve !

 

[N-Channel]

Thanks. Since Radio Schmuck, uh, I mean Radio Shack stopped carrying their rub-on dry-transfers, I have been stuck for a good source of sheets. For now, I have to rely on a single retailer across town, and they're not the easiest people to deal with. RS: 4 sheets assorted patterns for USD$1.99. These guys: 3 small sheets, lines, donuts, or IC sockets ONLY, USD$2.50/pkg. So, if I want some donuts, lines, IC Pads, and some other patterns, I'm for at least USD$10.00 before taxes. UGH!

 

[Tolik]

So, if I want some donuts, lines, IC Pads, and some other patterns, I'm for at least USD$10.00 before taxes. UGH!

I understend you...
If I want something more than carbon resistors or BC337 that avaible from single retailer in my town , I`m $8-10 for shipping & handling only in very best case That was not so painful if I was living in the kind of countrys like Ethiopia or Kongo, but I`m living in country that dealing with the USA & Russia in aerospace & military projects, and I need to order simple parts from overseas

 

[sss]

I understend you...
If I want something more than carbon resistors or BC337 that avaible from single retailer in my town , I`m $8-10 for shipping & handling only in very best case That was not so painful if I was living in the kind of countrys like Ethiopia or Kongo, but I`m living in country that dealing with the USA & Russia in aerospace & military projects, and I need to order simple parts from overseas

in haifa and tel aviv u have better alternatives


😉