I'm an absolute analog circuit designer and developer with great practice in sound engineering. I used to be a sound engineer. I was a research engineer at a plasma physics laboratory. (High Voltage, Vacuum Technique) I know the electron tube technology. For many years I've been upgrading microphones , radio microphones to theaters and movie engineers. My hobbies studio condenser microphones upgrade. I do not have a sports hobby, except for target shooting. I have a well equipped electronics laboratory with serious instruments. (Neutrik A2 Audio Test & Service System, Tektronix Oscilloscopes, Current Probes, R & S Signal Generator, HP Other Instruments, Even Small lathe. I'm a high-tech master except for computing.