| Notes |
The crystal replaced by a valve, reaction, a simple reaction circuit, an aperiodic grid circuit, loosely coupled circuit with reaction, another loose-coupler circuit, a good "all-purpose" circuit, capacity reaction circuit, another capacity reaction circuit, Armstrong's regenerative circuit, Armstrong circuit using variometer, Armstrong's super-regenerative circuit, H.F. transformers, a simple H.F. two-valve circuit, reaction without interference, a crystal circuit with reaction, a circuit for very short waves |