Instrument Meter Specialties

2108 B West Magnolia Blvd
Burbank, CA 91506
Phone: 800-926-3837 FAX: 818-841-2379

Specifications:
A low range ac voltmeter suitable for connecting across a 600 ohm line and self contained except for requiring an external 3.6k ohm resistor. Calibrated for use with a 3.6k ohm resistor 4vu above the scale marking so that the reference deflection (0vu) is produced by a signal 4vu above 1mW in 600 ohms (1.228v).
The performance of the meter is based upon the requirements of BS 6840: Part 17:1991, IEC 268 - 17: 1990. The dynamic characteristics quoted, which requires the response time to 99% of reference deflection (0vu) to be 0.3 seconds +/-10% with an overswing of at least 1.0% but not more than 1.5% are not fully met.
The overswing, because damping is not so tightly controlled but allowed to spread within normal design restraints, can vary between deadbeat to 5%. To specify the dynamic characteristics in terms of time to 99% of 0vu under such circumstances would give an unrepresentative measure of the speed of response. For this reason the time to reach -3vu with a steady reading of reference deflection (0vu) has been taken as a more realistic measure.

The following comparison can be made based on a rise time to -3vu with steady deflection of 0vu:

Conventional vu meter            0.13 - 0.15 seconds

AL20 & AL20SQ                             0.14 - 0.18 seconds

The AL20SQ Audio Level analog panel meter complements the proven and popular Presentor Series.  The meter offers a performance not significantly different from full specification vu meters to meet today’s specific audio market requirement for both quality and distinctive ‘retro’ styling at an affordable price.

Features and benefits

• Available in one popular size with front of panel mounting and secured by either four fixing screws (model AL20SQ), or an optional locking ring (PN:2387208 for model AL20).

• Constructed with gloss black phenolic molded front with glass window and high impact translucent rear body molding.

• Taut band core magnet movement incorporated as standard.  This rugged movement makes these meters equally suitable for portable or fixed audio applications.  There is no calibration effect when mounted on a ferrous panel.

Pointers and dials

The combination of a ‘pear’ shaped pointer and conventional arc scale on translucent buff colored dial results in an easily read meter, even when monitoring a row on a large console.  A white dial can be specified if required.  The standard scale is based on the vu ‘A’ scale, but the ‘B’ scale with the ‘percent’ reading at the top can be supplied to order at no extra cost.

Zero adjuster

Positioned on the rear as standard.

Certified drawings

Available on request.

Operating Temperature

-25C to +55C

Illumination

This is available as a rear mounted factory fitted option.  The unit contains a 6mm ‘festoon’ style lamp available in 6V, 12V, or 24V.

Terminals

Flying leads 125mm/5” long are standard, but 6mm tabs are available.

Dimensions

Terminals

Illumination