The Model 177 is a rugged benchtop ratemeter with an alarm. This instrument is very popular for frisking operations at stations where line power is available. It can also be used in portable applications for up to 50 hours using the internal rechargeable battery.
The Model 177 supports GM and scintillation type detectors and displays the results on a linear readout analog meter. The audio alarm is adjustable from 0 through 150% of full scale, and is factory set to latching. Reconfiguration to non-latching can be accommodated via a minor internal change.
Front-panel controls include a four-position rotary switch for selecting each detector decade, an alarm set control, an audio volume adjust, fast/slow response switch, power on/off switch and pushbuttons for count reset, battery test, high-voltage test, and alarm test. The back panel contains the power cord connection and a 9-pin type "D" plug, 6 to 9.6 volts power output, alarm output, pulse output, and a recorder output.