STABILITY STUDIES OF QUARTZ CRYSTALS FOR SATELLITES
Abstract
OVER 100 100-Mc AT-cut quartz resonators were made and stored at 0 C and 60 C or cycled through the temperature range 0 C to 60 C once daily. The units have consisted of resonators operated at the 5th, 7th, and 9th overtones and were plated with Ag, Al, or Cu. Frequency measurements have been made by a bridge and counter method. The standard frequency was derived from a bank of 3 oscillators monitored against the 18kc signal of radio station NBA, Balboa, Canal Zone; an Atomichron served as a standby standard. The NBA signal was received in Atlanta, Ga., to an accuracy of 6 parts in 10 to the 10th power. The more stable units have been 9th overtone units coated with Ag. Several of these have held + or -5 parts in 10 to the 8th power more than 180 days. Radiation damage was conducted by exposure of 12 stable 9th-mode units to approximately 1 x 10 to the 6th power rad/hr. A dosage for 30 min at the highest intensity available resulted in a negative frequency shift of 5 to 10 ppm. Aging at 60 C thereafter was upward at a rate of about +2 x 10 to the -8th power per day. For a dosage of one hr at a lower intensity, more in agreement with that to be expected in the Van Allen Radiation Belt (2 x 10 to the 4th power rad/hr.), shifts of about -2 x 10 to the -7th were experienced. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 30, 1961
- Accession Number
- AD0264308
Entities
People
- R.b. Belser
- W.h. Hicklin
Organizations
- Georgia Tech