Pultec EQ inductor dissection ;)

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Nikolay

Well-known member
Joined
Dec 22, 2004
Messages
176
Hi let's go! :)

The beginnigh I take one inducor to make pultec's EQ and I naked the bobin :oops:

Here are the inductor:
http://www.picvalley.net/u/83/82540_978.JPG

I remove the metal cramb and take the bobin. Here are all parts:
http://www.picvalley.net/u/83/82542_982.JPG

...and the bobin
http://www.picvalley.net/u/83/82541_980.JPG

Wire.
http://www.picvalley.net/u/83/82545_994.JPG
I measure wire thickness 0.25mm:

Some ferrite dimensions:
http://www.picvalley.net/u/83/82543_985.JPG

I use these meters:
http://www.picvalley.net/u/83/82552_418.JPG

To get these values of inductance and DC resistance.
http://www.picvalley.net/u/83/82544_991.GIF


That's all folks :green:
 
:shock:
CJ, you´ve got a brother across the pond.

thanks, mate
Pretty low DCR they have at cinemag. It´s much better than the Toko alternative which everybody (and me) used on the Gpultec.
:thumb:
 
Inductance is inductance, but yeah, the original was probably a tape wound or powder core torroid. I guess if you wanted to go for the original sond you should wind it like the original, but those pot cores can sound good.
One neat thing about the pot core is that you have a zillion different types of baked goods to chose from, wherre as, with the tape wound, you have 2 mil, 4 mil, and 12 to 14 mil 50/50 or grain. As opposed to an old Phillips or Seimens catalog.

Here is a ferrite baker:
 
Nice Dissection - Thanks!

Is it possible to see any markings on either of the two the pot core halves to determine the exact type and/or maker of ferrite?

Jakob E.
 
There was a place in England that burned down a while back. it was a ware house full of ferrite. :cry:

I hope they got back up.

Lead hookup is a lot easier with the pot cores, you do not have to loop wire every 87.5 degrees, like you would on a toroid winder.

I can wind some originals, if we can figure out the core.

For people who want to restore the eq to it's original state of ugliness.

:grin:
 
[quote author="CJ"]There was a place in England that burned down a while back. it was a ware house full of ferrite. :cry:

I hope they got back up.[/quote]

Mainline, yes. Nice company - and they're slowly working their way back:

http://www.mainline-group.com/

Jakob E.
 
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