The spike in the transmit-receiver (TR) tubes

The spike leakage signal from high-Q and band-pass tr tubes was recorded as a function of time by using high-speed oscillographic techniques. Transients as short as 0.5 millimicro-seconds (0.5 × 10
^-9
seconds) were resolved. The variation of the 1B24 high-Q tr spike was determined as a function of time for several experimental parameters including the gas type and pressure, initial number of electrons in the tr gap, and peak incident power supplied by the transmitter. Oscillographic recordings show the tr spike leakage power from a commercial gas-filled 1B24 tr tube rises to a peak of 0.3w in a time interval of 6 mµsec. The spike leakage power from a 5863 three-gap band-pass tr tube rises to a peak of 3.6w in 7.5 mµsec. Threshold of microwave gas discharge breakdown measurements in helium gas are used to determine the electric field intensity in the 1B24 tr gap as a function of the waveguide power. From this, the electron motion during the spike interval is calculated. The results indicate that production of electrons in the gap can occur through ionization of the gas by the electrons' radio frequency energies, and by secondary emission at the gap surfaces, as well as through ionization of the gas by the electrons' energies of random motion.