Before revision: Resistor–transistor logic (RTL) (sometimes also transistor–resistor logic (TRL) ) is a class of digital circuits built using resistors as the input network and bipolar junction transistors (BJTs) as switching devices.
After revision: Resistor–transistor logic (RTL) , sometimes also known as transistor–resistor logic (TRL, ) is a class of digital circuits built using resistors as the input network and bipolar junction transistors (BJTs) as switching devices.