Designed to read zero VU or 100% with 1.228 volts applied to the instrument and the 3600 ohm series resistance; this represents 4 DB above 1 milliwatt in 600 ohms.
The combination of a special copper oxide rectifier and an extremely sensitive movement with special magnetic system gives very high sensitivity.

Scale:
Type “A” Scale reads “-20 to +3” in type on the top of the arc, with “0-100” on the bottom of the arc in type.
Type “B” Scale reads “0-100” in type on the top of the arc, with “-20 to +3” in type on the bottom of the arc.

Accuracy: 2%.
Dials: 100 degree arc, black lettering on white or buff background.
Pointer: Knife Edgee.
Movement: Spring loaded pivot and jewel movement that assures maximum torque and readability.
Mounting: Surface mount.
Case: Bakelite..

General
Operating Temperature: 32°F to 104°F ( 0°C to 40°C).
Storage Temperature: -4°F to 131°F (-20°C to 55°C).
Relative Humidity: 20% to 80%RH (Nominal Use).
Meter Approvals: ANSI C39.1.
Origin: Made in USA

Publication: Why Sound Engineers Still Prefer Analog VU Meters in Recording Studios

Publication: VU Meters in High-End Sound Systems

Designed to read zero VU or 100% with 1.228 volts applied to the instrument and the 3600 ohm series resistance; this represents 4 DB above 1 milliwatt in 600 ohms.
The combination of a special copper oxide rectifier and an extremely sensitive movement with special magnetic system gives very high sensitivity.

Scale:
Type “A” Scale reads “-20 to +3” in type on the top of the arc, with “0-100” on the bottom of the arc in type.
Type “B” Scale reads “0-100” in type on the top of the arc, with “-20 to +3” in type on the bottom of the arc.

Accuracy: 2%.
Dials: 100 degree arc, black lettering on white or buff background.
Pointer: Knife Edgee.
Movement: Spring loaded pivot and jewel movement that assures maximum torque and readability.
Mounting: Surface mount.
Case: Bakelite..

General
Operating Temperature: 32°F to 104°F ( 0°C to 40°C).
Storage Temperature: -4°F to 131°F (-20°C to 55°C).
Relative Humidity: 20% to 80%RH (Nominal Use).
Meter Approvals: ANSI C39.1.
Origin: Made in USA

Publication: Why Sound Engineers Still Prefer Analog VU Meters in Recording Studios

Publication: VU Meters in High-End Sound Systems