Do you have a question about the Eico 378 and is the answer not in the manual?
Details the purpose and operation of each control on the front panel.
Describes the power supply circuit with rectifier and filter.
Explains the oscillator circuit and amplitude stabilization method.
Details the attenuator system for reducing signal levels.
Describes the meter circuit and its voltage/db scales.
Describes preliminary checks and power-up procedures before full adjustment.
Details the specific steps for calibrating the instrument's meter.
Describes visual inspection and tube voltage checks for troubleshooting.