Instruction manual for Gunn-diode microwave cavity ammonia monitor

Technical Report · Tue Jun 28 04:00:00 EDT 1977

DOI:https://doi.org/10.2172/7210202· OSTI ID:7210202

Hrubesh, L. W.; Maddux, Jr., A. S.; Johnson, D. C.

The Gunn-diode microwave cavity instrument is a self-contained (the vacuum pump is external) microwave spectrometer for the specific detection and monitoring of ammonia gas in air. A solid state microwave source is used together with a high-Q resonant microwave cavity which is both the frequency selecting device for the source and the sample container through which the sampled gases pass. The ammonia absorption transition at 23,870.1 MHz is monitored continuously with this instrument. The monitoring frequency is stable to one part in 10/sup 9/ so that the system only responds to NH/sub 3/ absorption--there are no known interfering gases. The instrument was designed for simple operation and easy calibration. Except for the calibration procedure, the instrument operates automatically from turn-on. A four-digit readout is supplied on the front panel and it reads the concentration of ammonia directly in parts-per-million over a range of from 0.00 to 20 ppM. A 0 to 10 volt output is also available at the rear panel for recording data on an external recorder.

• Research Organization: California Univ., Livermore (USA). Lawrence Livermore Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 7210202
• Report Number(s): UCID-17513
• Country of Publication: United States
• Language: English

Related Subjects

440300 -- Miscellaneous Instruments-- (-1989)
47 OTHER INSTRUMENTATION
500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ABSORPTION SPECTRA
AIR POLLUTION
AIR POLLUTION MONITORS
AMMONIA
DESIGN
ELECTRONIC EQUIPMENT
HYDRIDES
HYDROGEN COMPOUNDS
MEASURING INSTRUMENTS
MICROWAVE EQUIPMENT
MICROWAVE SPECTRA
MONITORING
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
POLLUTION
SEMICONDUCTOR DEVICES
SEMICONDUCTOR DIODES
SPECTRA