Amplifier Research 999

The 999 Leveling Preamplifier provides rf gain control over an extended bandwidth of 1-1000MHz (25 dB minimum), pedestal out of adjustable width, blanking output, rf output delay (also adjustable) at the conclusion of a blanking pulse to permit the power amplifier to settle before an rf signal is again applied. These blanking and pulsing features make the unit particularly useful in NMR spectroscopy. The instrument has a minimum power output of 10 mw and a nominal input and output impedance of 50-ohms.