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m177-56_pic-e
m177-56_pic-em177-56_pic-cm177-56_pic-bm177-56_pic-am177-56_pic-d

Model 177-56

Alpha/Beta Benchtop Counter

Part Number: 48-1323

Features

  • Operates with Two Detectors: Scintillator for Alpha, GM for Beta
  • 4-Range Meter
  • Linear Analog Scale Readout
  • 50-Hour Rechargeable Battery

The Model 177-56 is a rugged benchtop ratemeter with a dual-detector system, allowing the selection of either alpha or beta readings, and works as an alpha/beta frisking station. The instrument supports GM and scintillation type detectors and displays the count rate on a four-decade, linear readout analog meter. It can be used where line power is available or in portable applications for up to 50 hours using the internal rechargeable battery.

Front-panel controls include power on/off switch, volume control, a four-position range selector switch, fast/slow response switch, and push-buttons for count reset, battery test, and high-voltage test. On the back panel are the power cord connection, a 9-pin type "D" data plug, and calibration controls.

 

  • Specifications
  • Options
  • Documents
  • Replacement Parts
  • Specifications
  • Options
  • Documents
  • Replacement Parts

Specifications

Compatible Detectors Scintillation (alpha), GM (beta)
Linearity Within 5% of full scale;
Typically ±2% of full scale reading when measured with an electronic pulse generator
Battery Dependence Meter reading varies less than 3% within battery check limits
Meter Dial 0 - 500 cpm, 0 - 1.5 kV, BAT TEST
Meter 1 mA, size 6.4 x 6.4 cm (2.5 x 2.5 in.), DC movement
Multipliers x1, x10, x100, 1k
Response Toggle switch control selects FAST (2.2 s) or SLOW (22 s) response, for 90% of full-scale reading
Reset Push-button to zero meter
Calibration Controls Accessible from back of instrument (protective cover provided)
High Voltage Alpha: Variable from 400 to 1500 V
Beta: 900 V
Input Sensitivity Alpha: Adjustable from -10 to -100 mV
Beta: -10 to -25 mV (fixed)
Audio Unimorph speaker with volume control located on the front panel, provides click-per-event audio
Data Out 9-pin series "D" connector allowing for external connections of the following items:
  • Battery
  • Unregulated supply
  • Instrument common ground
  • Pulse out
  • External background subtract
  • Recorder output
Recorder Output Adjustable from 0 to 1.25 V at 1 mA
Unbuffered Output May be used to externally add to or subtract from the meter reading
Power 95 to 250 VAC wall transformer and 6 V gel-cell (sealed lead-acid) battery
Battery Life Approximately 50 hours with a fully charged battery
Fuse 1 amp 3AG fuse
Connectors Series "C" connector for beta GM detector
MHV connector for alpha scintillator detector
Finish Powder coat paint
Size (H x W x L) 16 x 20.3 x 17.5 cm (6.3 x 8 x 6.9 in.), excluding handle
Weight 1.9 kg (4.2 lb) with battery

Options

OptionDescriptionPart Number
4 - 20 mA Output (Isolated) Analog output signal. 4347-437
Shelf (or Wall) Bracket Mounting bracket for the Model 177-Series of instruments. 7172-078-02

Documents

  • Data Sheet
  • Product Manual

Replacement Parts

DescriptionPart Number
AC Rustrack Cable 8303-387
DC Rustrack Cable 8303-426
Meter Assembly 4173-166
Rechargeable Batteries 21-9385

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