Model 19A

microR Survey Meter with Alarm

Part Number: 48-2117

Features

High Sensitivity to Gamma
Range: 0 to 5 µSv/h (0 to 500 µR/hr)
Analog Meter with Alarms
Rugged
Splashproof Protection for Outdoor Use

The Model 19A is a highly sensitive gamma microR meter with an alarm employing an internally housed 2.5 x 2.5 cm thick (1.0 x 1.0 in.) NaI detector. The display is an analog logarithmic meter scale with a range of 0 to 5 µSv/h (0 to 500 µR/hr), so switching between scales is not necessary as on many other instruments.

The front panel controls include a three-position rotary switch for Off, Battery Check, and On; an Audio On/Off switch; and an Alarm Reset button. A red alarm light is mounted on the front panel and is accompanied by an audio signal. The alarm circuit is adjustable over the entire scale range.

The cast aluminum instrument housing with a separate battery compartment and accompanying metal handle offer an industrial robustness and quality that promote long lasting protection and instrument life. The Model 19A is a complete turn-key system and includes two "D" cell batteries.

Specifications

Application	Low-level (μR) gamma survey
Detector (D x L)	NaI(Tl) scintillator, 2.5 x 2.5 cm (1 x 1 in.)
Detection Range	Background to 500 µR/hr
Sensitivity (¹³⁷Cs gamma)	Approximately 17,500 cpm per μSv/h (175 cpm per μR/hr)
Energy Response	Energy dependent (see Energy Response Curve)
Linearity	Reading ± 10% of true value
Meter Dial	0 - 5 µSv/h (0 - 500 μR/hr) dual colored logarithmic scale, BAT TEST (Meter Faces tab lists other available meter faces)
Meter	6.4 cm (2.5 in.) arc, 1 mA analog type
Controls	Rotary Knob Selector: Instrument Off, Battery Check, Instrument On Audio: ON/OFF switch, built-in unimorph speaker (greater than 60 dB at 61 cm [2 ft]) Alarm Reset: Pushbutton reset alarm Calibration Controls: Accessible from front of instrument (protective cover provided)
Response	Dependent on number of counts present (typically not greater than 7 s from 10% to 90% of final reading)
Alarm	Indicated by red lamp and audible tone (alarm audio overrides the audio ON/OFF switch)
Alarm Range	Zero to off-scale
Working Environment	Splashproof shields for outdoor use
Temperature Range	-20 to 50 °C (-4 to 122 °F) May be certified for operation from -40 to 65 °C (-40 to 150 °F)
Power	2 each “D” cell batteries (housed in sealed compartment that is externally accessible)
Battery Life	Typically 600 hours with alkaline batteries (battery condition can be checked on meter)
Construction	Cast and drawn aluminum with beige powder coat finish
Size (H x W x L)	19.8 x 8.9 x 21.6 cm (7.8 x 3.5 x 8.5 in.) with handle
Weight	2.1 kg (4.5 lb), including batteries

Meter Faces

This table lists the most commonly used meter faces. Others are available upon request.

Meter Face	Image (click to view larger)	Description
202-1034		0 - 500 µR/hr LOG BAT TEST
202-1040		0 - 50 µSv/h LOG BAT TEST
202-1064		0 - 5 µSv/h LOG BAT TEST

Options

Option	Description	Part Number
Lighted Handle	Handle with LED to illuminate the instrument display.	4464-154
Shoulder Strap	Adjustable nylon shoulder strap.	4363-413
Plastic Disk Check Sources	General purpose check sources used to check instrument response.	Depends on source material and activity.

Replacement Parts

Description	Part Number
NaI(Tl) Scintillator glued to PMT, Non-Based with Voltage Divider	2004-033
NaI(Tl) Scintillator with PMT, Non-Based with Voltage Divider	40-5154
Detector Assembly (Includes 2004-033)	47-1574