The amplifier is designed around the ECL82 tube, which includes both a triode and a pentode in one package. The ECL82 is practically an amplifier in a tube: it was designed for low-cost ...
[Mikremk] demonstrates this with a simple but effective amplifier using a PCL82 triode-pentode. It’s a conventional tube amplifier circuit in which the triode is a preamplifier for the pentode ...