Portable Audio Signal Generator - Radio Design Labs PT-ASG1

The PT-ASG1 is a portable or benchtop audio oscillator used in applications requiring a stable audio signal source for system verification, alignment and testing. The internal oscillator operates at 700 Hz allowing aural monitoring of the signal without the fatigue associated with oscillators running at a higher frequency such as 1000 Hz. The 700 Hz signal falls in the passband of an audio system and is easily distinguished from either 400 Hz or 1 kHz signals. The oscillator output is compared against an internal temperature-stable reference in a gain controlled loop that adjusts the final output level with stability suited to accurate bench top audio testing.

Two outputs are provided on the PT-ASG1. The XLR balanced output is front-panel switch selectable for MIC or LINE level. The line level is factory set to +4 dBu, but can be programmed to +6 dBu. When the front-panel level switch is set to MIC, the XLR output level is set to -46 dBu, 50 dB below +4. The unique output network produces the same output level into low impedance (200 Ω) and higher impedance (>1 kΩ) mic preamps.

The PT-ASG1 operates either from an internal 9 volt battery or from an external 12 Vdc to 30 Vdc supply. Test leads and a bench top support bracket are included. A switch in the battery compartment allows the user to preset the balanced line-level output to +4 dBu or +6 dBu.