imsai 2

From: Dave Dameron <ddameron_at_earthlink.net>
Date: Wed Aug 18 18:54:35 1999

At 06:52 PM 8/18/99 -0400, Allison wrote:

>As someone that has wound audio and power transformers from scratch it's
>a pretty trivial task and can be very useful. Used to be a time the
>ARRL (USA) Handbook for Radio Amateurs had all the tables. Though given
>a random core it's pretty easy work all the numbers out after finding out
>if it's big enough.
>
>Allison
Yes. Good numbers to start with for power transformers are (US
measurements, I am sure there are equivalent ones in use elsewhere):
6 turns/volt/square inch of core.
Wattage = 32*(square inch of core)^2
For AWG 23 wire, 1 Amp and area changes by 2x for every 3 gauge numbers.
Winding space is easy to figure out with standard "EI" laminations.

Of course small transformers such as in some wall warts would be a pain!
-Dave
Received on Wed Aug 18 1999 - 18:54:35 BST