Perkin-Elmer Cobra 5002 Gamma Counter - pre-owned

Cobra 5002 Gamma Counter.........................$4,995 + shipping/handling

Specifications

Height: 28 inches
Width: 27 inches
Depth: 32 inches
Weight: 400 lbs

Electrical Requirements: 100 to 122 VAC, 10% at 50/60 Hz

A surge protector is recommended. The system provides automatic restart after a power failure.

Environmental:

Operating Temperature: 59 to 95 degrees Fahrenheit
Relative Humidity: 30 to 85 percent (non-condensing)

This instrument should be located away from all sources of radiation (X-ray equipment, radiation storage vaults, etc.)

Detectors:

The detectors consist of thallium activated, sodium iodide crystals of the through-hole design. Each crystal is optically coupled to a photo multiplier tube (PMT)

Detector size for Cobra 5002:

2 inches

Shielding:

Approximately 2 inches of lead shielding surrounds the detector

Energy Range:

Preset Regions:

I-125: 15 to 75 keV
Co-57: 75 to 165 keV
Cr-51: 240 to 400 keV

Manual (custom) Regions:

15 to 2000 keV

Use of infinite setting for the upper limit of the custom regions allows you to count high energy nuclides, but individual channel discrimination is only provided to 1000 keV. When counting high energy radio nuclides, detector to detector and sample changer deck to detector cross talk may become an issue.

Additional Preset Regions for Cobra Model 5002:

Co-60: 1050 to 1550 keV
Se-75: 60 to 467 keV
I-131: 260 to 470 keV
Fe-59: 940 to 1400 keV
Na-22: 433 to 1417 keV

Efficiency for Cobra 5002:

I-125 > 72%

Use of glass tubes may lower the efficiency to the point where a failure message may be reported. If you use glass tubes for some assays and plastic tubes for other assays, it is recommended that you use the manual IPA method as described in Chapter 3 (page R342) of the reference manual. The manual method allows you to control the collection of IPA data so that erroneous efficiency failure messages are not reported.

Resolution:

Cobra 5002: I-129 </= 32%

Background:

Instrument background specification as counted in preset regions with counting chambers empty.

Cobra 5002: I-125 </= 50 CPM

Spilldown:

Co-57 into I-125 preset region (at elevator position 1): <3.5%