The Level Meter LM21 is a handheld battery powered instrument designed to perform audio or voice testing for sound recording systems or sound programme circuits. The main characteristic of the LM21 is the large number of facilities provided in such a small package.

Great care has been taken to achieve easy operation of this instrument. All functions are activated by one button. Most instruments of this complexity revert to menu tree mode selection thereby necessitating handbook guidance or on screen help. The LM21 can be operated without these aids.

The following features are provided:

• 85 hours operation with dry cells
• Battery voltage monitor
• 20 kHz level meter
• CCIR Rec 468-3 Quasi Peak Weighted Noise
• CCIR Rec 468-3 Unweighted Noise
• 0.1 to 100 V dc voltage measurement
• 400 Hz automatic distortion measurement
• 400 Hz 0 dBm,-10 dBm oscillator
• 600 W , 1200 W and 100 kW impedance
• Audio monitor