6SN7 Preamplifier (T1105E)

This preamp circuit has a typical configuration as found in a 1946 publication. Supply voltages are indicated.

Double limit detector (CB9589E)
Found in ancient American documentation, this circuit uses some components from the time, such as...
Operational Compensated LM101 (CB20153E)
In the figure we have the way to compensate an operational amplifier. The circuit is valid for...
LED Integrated Driver For 3 V (CB12597E)
With this circuit, it is possible to excite a white LED or another type of high brightness with...