Creating a custom voltage on a toroidal transformer

[William Gaatjes]

Meh, i tried to find some spice models of the transistors i got and found a lt wiki library, but i get the feeling that there have been added random or faulty numbers. And there is the issue of various spice versions. .

http://ltwiki.org/?title=Standard.bjt

Intermezzo
To those interested :
In the installation directory of LTspice, there is a lib directory where standard.bjt can be found. Here all transistors are listed. It is a text file, so editing is easy since it can be opened in any text editor. And other transistors can be added. Please make a backup when modifying it, because ltspice might copy over the edited standard.bjt file when updating models. It is handy to keep all added models at the top of the text file and add some comment at the end so you know what you added if you are going to add models of your own. The circuit suffers from oscillation.
End intermezzo

I found the BD907 that is very similar to the BD911 but it is like a short circuit in the simulation. I found out that the BD907 spice model at the wiki has a ver high gain AF(BF) of over 300 while in reality it is much lower. Luckily i have some documentation what all the variables mean. Maybe i can fix the model. I got it to work already, but it is far from operational.

http://dl.dropbox.com/u/45177488/electronics/LTSpice/scad3_ltspice.pdf
For bipolar transistors ,page 145.

Handy dandy library thread :
http://forums.anandtech.com/showthread.php?t=2250963

 

[William Gaatjes]

Anyway, i will see if i can make a proper schematic in a real schematic program.

 

[William Gaatjes]

The transformer is finished. It is now comprised of 4 coils of 14.4V AC @ 6.44A.
One coil of 33V AC @ 200mA. To power the opamp circuits.
One coil of 9V AC @ 300mA. To power the PM435 panel meters and backlights.
The current for the last two coils are an estimated guess. In reality, i need far less. About 25% of the current.