In article , "Mike Czuhajewski"
writes:

For years Amidon was pretty much the only place hams bought ferrite and
powdered iron cores. A different company sprang up a few years back,
composed of some former Amidon associates as well as former Amidon
employees, and they are selling the same things. (Their reasons for going
out on their own involves, I believe, discontent with their relationships
with their former company, something which is hardly uncommon in the
business world.)

The name is Bytemark, or more properly CWS Bytemark, since it merged with
CWS a while back.

The URL is http://www.bytemark.com/ and the site has a lot of technical info
on the toroids.

At least one of them is a ham, Tracy Markham, N4LGH, who was the driving
force behind the original Bytemark. He's a homebrewer and was active on the
QRP mail reflector for a few years.

Amidon Associates started up in Burbank, CA, in 1963 as a small
business by Bill Amidon, then with NBC at the NBC western Hq
complex in Burbank. The product was small-quantity reselling of
Micrometals powdered-iron and Fair-Rite ferrite products, packed
one to a few in small plastic bags found on display racks in hobby
electronics stores.

Micrometals was begun in 1951 in Orange County (just south of
Los Angeles County that includes Burbank). Micrometals is a
powdered-iron product manufacturer who sells in large minimum
quantities. Micrometals is also the origin of the Q curves (found in
limited quantity in Amidon packets) and the part number format that
so many now associate with Amidon. Micrometals doesn't sell
directly to hobbyists (unless they order a minimum quantity) but
Amidon Associates did/does. Amidon reselling was and is a good
service for hobbyists.

It is my understanding (but no proof) that Bill Amidon was a ham.
His name doesn't appear on a QRZ search. For a part-time
business started 40 years ago, Amidon Associates changed
addresses a couple times and seems to have been purchased by
another group and turned into "Amidon Corporation." That company
has a website at http://www.amidoncorp.com and you can find
many, many Q curves (good for reference) on one of their inernal
pages plus a lot of data good for planning powdered-iron toroid
or ferrite applications. Amidon Corporation is headquartered in
Costa Mesa, CA, and claims it has "manufacturing" (probably
like a lot of distributors claim pseudo-ownership of the companies
on their product card). They will sell small quantities of forms,
wire, 3M tapes, teflon tubing, the older Amidon Associated kits,
etc., and have an 800 number listed "for hams."

Yes, CWS Bytemark exists also, headquartered in Santa Ana,
CA. [all the powdered-iron companies have gravitated to Orange
County? :-) ] Under the "Parent Company" there, it comes out
that Coil Winding Specialists owns them and deals or resells a
number of frequency products, some of them from Asian
manufacturing locations.

I'm not going to delve into "business practices." Such doesn't
have any bearing on "Low Loss Toroids." I do know that Amidon
Associates had a very handy and useful service for hobbyists
(myself included) in reselling Micrometals products. I do know
that Micrometals has a quality product after specifying orders
from them at work. The original Micrometals toroidal form ID
format has now assumed a "Texas Instrument" kind of status in
that many others use their same nomenclature...like "7400" is
a quad 2-input NAND logic IC package identifier to all regardless
of who actually made it. :-)

Len Anderson
retired (from regular hours) electronic engineer person