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Over the years, Ludlum Measurements has written several technical articles in support of our products. These articles cover topics such as troubleshooting and repair tips, calibration techniques, and other information related to radiation detection and instrumentation.

Have you ever really needed an extra probe or cable badly, and after receiving it, found it had the wrong connector?

If the answer is yes, then this problem can be solved with a little help from you.

We frequently get questions about our gas proportional detectors, and are glad to offer information on how we "check out" this product. In the following example, we will demonstrate the check-out procedure for the Ludlum Model 43-68 gas proportional detector.

The majority of problems we encounter with returned instruments in the Ludlum Repair Department require simple solutions. Dirty or corroded contacts (especially battery contacts), damaged cables, loose connections, and other types of mechanical problems are the leading cause of instrument failure. Although electronic component failure is a possibility, it is infrequent in comparison.

Occasionally a customer may experience a problem with condensing humidity causing dew or frost inside the instrument. Dew will form inside an instrument when it experiences a large decrease in temperature, such as moving from indoors to outdoors.

Many of our customers inquire about using scintillation and GM detectors interchangeably with the same instrument. To make this possible, a few extra steps must be taken because of the difference in operating voltages of these two types of detectors.

A common problem many of our customers experience is that of excessive background count when monitoring alpha radiation with scintillation detectors. This can be caused by light leaks or contamination of the detector.

Many of us have experienced the problem with punctures or "bad" seals (commonly referred to as "light leaks") in the thin mylar face of an alpha or beta scintillator. The problem symptom occurs with a detector that has been functioning properly and then suddenly will not respond to normal background count or a check source. The counting instrument appears to have "died", so it usually becomes the first suspect because of no response on the meter except maybe in the BAT position.

A common inquiry that we receive is the use of our survey meters and scintillation detectors with combination meter scales. The combination meter dial (counts per minute [cpm] and mR/hr) was designed so that a GM detector could be read in cpm and mR/hr simultaneously.