1840-A
The General Radio 1840-A Output Power Meter was introduced in Catalog R (1963). It remained available through Catalog 1978. It replaces Type 583-A designed in 1932.
The 1840-A is an audio power output meter rated at 20 watts maximum at 48 different load impedances in two ranges. Although rated at 20 W maximum, the manual describes how this figure can be extended to 200 W.
Specifications
- Power: 0.1 mW to 20 W
- Impedance: 0.6 Ω to 32 kΩ in 2 ranges
- Impedance Accuracy: Maximum error ±5% from 100 Hz to 10 kHz, or ±50% from 20 Hz to 30 kHz