On Feb 23, 12:24�am, "tack" wrote:
On Feb 21, 6:45 pm, wrote:
On Feb 21, 12:56?pm, "tack" wrote:

Say, can anyone point me to some information
on creating my own filter
chokes?

What size? Do you mean the type commonly used in
hollow-state gear - several henries at a couple of dozen
to a couple of hundred milliamps, insulated for hundreds
or thousands of volts?

If so, there is some info in older ARRL Handbooks and
in older versions of "Reference Data For Radio Engineers".

I can look up some details if needed.

Is there a source that anyone knows of for silicon-iron
core plates?

aka laminations

I googled "silicon iron transformer laminations" and found
a lot of stuff. Take a look. But I suspect that they may be
geared to production quantity orders.

One common source is the power transformer from an
old microwave oven. These are often welded together,
rather than bolted, and it may take a bit of work with a grinder to
get the core apart.

73 de Jim, N2EY

Thanks for the reply. *

You're welcome!

the term "laminations" escaped me. *

CRS disease......"Can't Remember......Stuff"

I have various old
transformers of various voltages, I hate to take any apart. *I think
that I will ohm them out and see if there are any open windings.

I agree that on not taking apart a good transformer!

There are enough bad ones that it shouldn't be necessary,
anyway.

*Yes,
hollow state technology, that's what I am in to. *Got started at a
young age. *My grandfather made and repaired radios before and after
the war. *He is not doing too well now. *I have most of his gear and
NOS parts and such. *Next weekend I'll be picking up his Riders. Got
his Drake TR-3 (AC-3 and DC-3 too). *I'll be getting that old Drake
back on the air! Anyway I'm planning some amp projects in the future
(After I clear a backlog of a dozen Transoceanics) *I have a few
chokes but I just wanted to try my hand at making my own power
chokes. *Made RF inductors in the past for SW receiver 1930's style.
I may be needin' up to 20 hy. *I'll be on Google later on researching
I suppose. *Just thought I'd mention about the choke cores in case
someone knew of a small qty source or had some to sell. *

I will look in my pile of stuff for bad ones that can be
dismantled for the iron.

I'm thinking
about taking a bundle of soft iron wires (bailing wire) insulating
them individually and corporately, then winding wire on. *Fold the
ends of the "core" together. *Perhaps a nice project with my son; help
him to learn.

The main problem I see with that is the magnetic properties
might not be as good, resulting in fewer henries than desired.

*I've got a 15lb spool of 30awg to experiment with.

EXCELLENT!

You might consider making some sort of winder. Chokes
typically involve thousands of turns, and you don't want to
just jumblewind them.

I will see what sort of basic choke data I can find in
my library.

Google my call, too.....

73 de Jim, N2EY