This circuit is from a 1980s Motorola documentation. The circuit can be made with modern equivalent components. The original circuit is for the 115 Vac (110 V) grid and has two settings.
This amplifier has a few Watt output, using old transistors. The speaker is 45 ohms, but with...
This circuit was found in an 80's Electronic Design. It amplifies TTL fast signals for a coaxial...
This circuit uses a Norton operational amplifier to generate 1 kHz pulses with a 1 to 60...