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The analysis of
these
permanent files can range from a snapshot picture of the
parameters to
a
time series analysis with plotting. Having the extreme long-term
history of the parameters has additional benefits, especially if that history extends
throughout the life of the standard.
USNO
has 45 standards
from the
100, 200,
300, 400, 500, 700, and 1000 production series. Each device has its own
"personality." Some characteristics have been correlated with production series.
This paper will present the general characteristics of the
USNO
devices and note
where they may differ.
The
parameters will be discussed in the order of their
output.
The
more important parameters will be noted and discussed in greater
detail.
THE PARAMETERS
There
are
22 parameter values available via the
RS-232
connection. These
parameters are: frequency offset, oscillator control percentage,
rf
amplitude 1
percentage, rf amplitude 2 percentage, Zeeman frequency,
C
field current, electron
multiplier voltage, signal gain percentage, tube oven voltage, tube oven t e m p e r a t u r e
error,
oscillator oven voltage, ion pump current, hot w i r e ionizer voltage, mass
spectrometer
voltage,
SAW
tuning voltage, DRO tuning voltage, 87 MHz
PLL
voltage, UP clock
PLL
voltage, +12 volt supply voltage, -12 volt supply voltage,
5 volt supply voltage, and internal temperature.
USNO
collects these data once per
hour. The information appears as:
MJD
48587 21:03:42
CBT
I D :
6-temp
Status
summary: Operating normally
Power source: AC
Log
status:
Empty
Freq Offset:
Oe-15
Osc. control:
RF amplitude 1: 20.2 96
RF
amplitude 2:
2 e m i Freq.
E-multiplier
:
CBT Oven:
Osc.
Oven:
HW
Ionizer:
SAW
Tuning:
87MHz
PLL:
+12v supply:
+5v
supply:
39949
H z
1870
V
6,2
V
-8.8
V
1.0
v
3.5
v
- 0 . 8
v
12.3 V
5.3
v
c-tieli cum:
Signal
G a i n :
CBT Oven
E r r :
Ion Pump
Mass spec:
DRO Tuning
UP clock
PILL:
-12v
supply:
Thermometer:
-1.67
%
19.9
%
12.137 mA
28.8
%
0,OO
c
0.2 uA
9.1 V
6.8 V
2.9
V
35.0 C
-12.4 V
50
7
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