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  • Ludlum Model 2402 Pocket-Size Survey Meter with Alarm

$930.00 $465.00

Out of stock

The Model 2402 is a pocket-sized ratemeter with an analog display that may be connected to a number of available detectors. This unit supports mR/hr exposure and cpm count-rate measurements. It also has a built-in audio and visual alarm. The metallic case and convenient size make this a nice tool to for a wide variety of applications.


  • Pocket-Size Ratemeter
  • Accommodates a Variety of Detectors
  • Audio & Visual Alarm
  • Metallic Case
  • Easy to Use


Indicated Use General purpose survey
Compatible Detectors GM, Scintillation
Range Detector dependent
Sensitivity Detector dependent
Energy Response Detector dependent
Meter Dial Typically 0 – 2 mR/hr
Multipliers x1, x10, x100
Response Time Typically 8 s from 10% to 90% of final reading
Alarm Detected radiation in excess of alarm point will trigger a red ALARM LED and a steady tone, whether in NORMAL or QUIET operating mode
High Voltage Adjustable from 550 to 900 Vdc, internal HV adjustment potentiometer
Threshold -35 ± 10 mV
Audio Click-per-event, may be turned off by moving selector to QUIET position
Power 9 volt battery
Battery Life Typically 250 hours with alkaline battery
Construction Drawn and cast aluminum with beige powder coat and printed membrane panel
Size (H x W x L) 4.6 x 8.4 x 13.5 cm (1.8 x 3.3 x 5.3 in.)


Add a Counts.Pro (see Ebay item 401468071255) to this meter for $499 and digitally record and easily share all your measurements (a $100 discount off the regular price when you buy one of our meters):

For a fraction of the price of a new meter, you can add a Counts.Pro and make your detectors more functional and easy to use than the most expensive meters available today.

We are the inventor of the Counts.Pro and regularly sell and service radiation detectors for nuclear industry, medical industry, and hobbyist clients. Counts.Pro uses a free App (iOS and Android) to record and share every count measured by any pulse generating radiation detector (GM, proportional, neutron, Scintillation). With Counts.Pro you can record your surveys for review and analysis, or take long term scaler counts to measure very low radiation level changes. Each data set includes every count measured by your meter, date, time, GPS, meter and probe info, operator inputs, and notes. Counts.Pro can measure 1 or 2 channels an includes an alarm feature for each channel.

Counts.Pro (which is a top level domain for more research) allows you to record all your measurements and works with any detector, old or new, that measures pulses. Counts.Pro uses the GPS in your smart phone (which can be enhanced to provide sub meter GPS) to record location. Gone are the days when you only see a dancing needle on your meter and wonder what the true reading is. Data is stored in a .csv format which can be opened by any typical spreadsheet. You don’t need special software to analyze what you get, so your files are “future proof”.

Counts.Pro gives you the following information:

On the App Screen while running:

Count Rate

Actual number of counts (Scaler)

Elapsed Time

Settings for count times (including infinite)

Start/Stop button

In the Data file (collected when you run a count time):
Date and time of EACH measurement

Actual counts in 0.25 second intervals with time stamp

Running count rate

Total Counts

Elapsed time

GPS location (if enabled) – 3rd party GPS units can be bought to give sub-meter GPS to iOS Devices.

Three user defined fields of unlimited length including the ability to take in measurement notes of observations.

Meter and probe model and serial numbers

Each count is stored on your device and can be emailed or shared using your smart device.

We have installed these in Ludlum Meters, Bicron Meters, Thermo Radeye’s, and other count rate meters. Counts.Pro turns your meter into something more functional than any meter you can buy for thousands more. With no software requirements, you are never held hostage to your data.

Additional information

Weight 2 lbs
Dimensions 9 × 9 × 9 in