GM Tube Unit - IPC [80895]

INTRODUCTION.

The IPC Irwin GM Tube Unit is an alternative to the GM Tube & Holder (BEES Code 80894, IPC Code IPC-6200-R) has been designed to work directly with our Timer Scaler & Frequency Meter (BEES Code 80054, IPC Code IPC-3342-T) via its TNC connection. It can also be used with many other makes of Scaler units simply by using a TNC to BNC adapter.

The GM Tube itself is contained in a robust tubular housing to provide protection to the delicate tube and is supplied with a front removable cap to provide additional protection when the unit is not in use. The tubular design of the housing also allows the option of clamping the unit to a retort stand. Electrical connection to the GM Tube is via a fixed 750mm coaxial cable to a TNC plug, also contained within the housing is a high ohmic value (10M) series resistor required by most Counter and Ratemeter (Scaler) units.

Please note: the original industry standard GM Tube PET connector is now obsolete (looks very similar to a TNC connector), therefore should any of your existing equipment have one these PET connectors fitted, IPC Irwin would be happy to carry out a retrofit, both to Timer Scalers and GM Tubes.

DESCRIPTION.

The GM Tube contained within the Holder is the industry standard type: LND712, with a 9.1mm dia. Detector window, making it suitable for all practical demonstrations and investigations as well as having an efficiency level suitable for detecting alpha, beta and gamma radiation.

Please note: This GM Tube does not meet the minimum detector window size as recommended in the CLEAPSS document GL:138 (Choosing a Geiger Muller Tube), to meet this requirement you will need to purchase the IPC Irwin GM Tube & Holder (IPC-6200-R), this has a detection window of 19.8mm and therefore meets the requirement.

INSTRUCTIONS.

Hold the GM Tube Unit in your hand and connect the TNC connector to the Scaler unit (use our BNC adapter if required), first making sure the HT voltage supply is set to minimum. Now remove the protection cover from the front of the GM Tube and place the radiation source to be used close to the detection window of the GM Tube (approx. 5 to 10mm from the window). Note: the mica detection window at the front of the GM Tube is delicate and therefore care should be taken not to damage it. We also recommend that the cover is refitted whenever the unit is not in use.

Now slowly increase the HT voltage supply unit the Scaler unit starts to count, the GM Tube should start to detect the radiation source between 350VDC to 450VDC, for ease of setting the audio (beep) on the Scaler unit should be switched on.

SPECIFICATIONS.

GM Tube Type = LND712

Connection Type = TNC on 750mm lead (TNC to BNC Adapter is available, IPC-6205-R)

Detection Window = 9.1mm diameter

Detection Source = Alpha, Beta & Gamma Radiation

Working Voltage = 350 to 450VDC

Internal Resistor = 10M

Mounting Method = Hand or Retort Stand Clamp

Dimensions = 125 x 22mm (overall)

Mass = 50 gram