- Power output of oscillators, amplifiers, preamplifiers, transformers, transducers, and low-frequency lines.
- Output impedance, by adjustment of the load to yield maximum power indication.
- Frequency-response characteristics of amplifiers, transformers, and other audio-frequency devices.
- *Power output of oscillators, amplifiers, preamplifiers, transformers, transducers, and low-frequency lines.
- *Output impedance, by adjustment of the load to yield maximum power indication.
- *Frequency-response characteristics of amplifiers, transformers, and other audio-frequency devices.
This instrument is basically a multi-tapped audio-frequency transformer with a fixed secondary load. Its two front-panel switches connect eight identical primary windings and six secondary taps in various combinations to provide a total of 48 different primary impedances.
The maximum power rating can be extended for any given impedance with the use of simple T-network attenuator, design data for which are supplied with the instrument.
Power Range: 0.1 mW to 20 watts in five ranges, 40 Hz to 20 kHz; maximum rating is reduced by up to 50% (at 25 Hz), depending on impedance selected. An auxiliary dB scale on the meter reads from -15 to +3 dB, referred to 1 mW. Impedance Range: 0.6 Ω to 32 kΩ in two ranges; yielding 48 individual impedances spaced approximately 2 apart. Accuracy Impedance: at 1 kHz, ±6% max, -0.5% avg; 70 Hz to 2.5 kHz, ±7% above 10 kW; 70 Hz to 5 kHz, ±7% below 10 kW; at 20 Hz, -15% max, -8% avg; at 20 kHz, ±50% max, ±12% avg When impedance is specified, accuracy applies at full-scale on all ranges and impedances at 1 kHz; when frequency ranges are specified, accuracy is at full-scale at ranges ≥20 mW at the specified impedances. When a frequency limit is specified, accuracy is at full-scale at all impedances Power: at 1 kHz, ±0.3 dB; 50 Hz to 6 kHz, ±0.5 dB; 30 Hz to 10 kHz, ±1 dB; at 20 Hz, -1.5 dB max, -1 dB avg; at 20 kHz, -5 dB max, ±1.5 dB avg. Waveform Error: Meter will indicate true rms with as much as 20% second and third harmonics present in the input signal. General Cabinet: Convertible bench cabinet, aluminum panel. Cabinet has extension legs to permit instrument to be used in a tilted position. Panel extensions, Type 480-P212 Adaptor Plate Sets, are available for relay-rack mounting. Dimensions: Panel - 12” W x 3.5” H (305 x 90 mm); depth behind panel - 6.5” (170 mm) Net Weight: 10.8 pounds (4.9 kg)