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  • Ludlum Model 9-4 Ion Chamber

$2,480.00 $1,240.00

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SKU: 214802845-3 Product Type: , Vendor:

Ludlum Model 9-4 Ion Chamber

The Ludlum Model 9-4 is a rugged air ionization chamber for performing beta-gamma dose rate measurements over a five-decade span ranging from 0 to 500 mSv/h (0 to 50,000 mR/hr). The ion chamber automatically compensates for changes in temperature and pressure. The chamber wall (including the instrument case) is 1000 mg/cm2. A 1000 mg/cm2 retractable beta shield allows beta measurement with a 7 mg/cm2 window.

The six-position selector switch selects Off, x10k, x1k, x100, x10 and x1. Other controls include an On/Off switch for a meter light, reset and battery test buttons, and a zero adjustment knob. An adjustable shoulder strap (included) provides a convenient and comfortable mode to carry the instrument during surveys.

The Model 9-4 is equipped with a serial interface for calibration. An optional calibration kit supplies the necessary interface cable, software, calibration can, pressure pump, and serial-to-USB converter.

  • 5-Range Ion Chamber
  • Ranges: 0 to 500 mSv/h (0 to 50,000 mR/hr)
  • 1000 mg/cm2 Retractable Beta Shield
  • Automatic Temperature & Pressure Compensation
  • Low-Battery Warning
  • High-Background Zero Capability
  • PC-Controlled Calibration

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 7 lbs

Ludlum Model 9