The Variables screen provides a list of 36 operating parameters. The parameters are described in the table below.
No. |
Name |
Description |
Example |
1 |
loop order |
loop design, first or second order; default = 2 |
2 |
2 |
cesium servo mode |
R+Z = oscillators locks to ramsey peak, c-field locks to zeeman peak R+T = oscillator locks to ramsey peak, c-field is constant |
R+Z |
3 |
4-state indicator |
00 = LOCK (no faults) 01 = INITIALIZATION (CRITICAL for TL1) 10 = MINOR ALARM 11 = CRITICAL ALARM |
00 |
4 - 8 |
5-place fault buffer |
refer to table of faults, Table 2-4 |
00,00,00,00,00 |
9 |
C-field adjust |
parts in 10-13 frequency adjustment using the cesium beam tube’s C-field |
+000 |
10 |
frequency adjust |
parts in 10-15 frequency adjustment using the digital synthesizer |
+001200 |
11 |
+25 V supply |
voltage (V) |
+25.3 |
12 |
loop time constant |
1 to 999, in tenths of seconds |
10.1 |
13 |
ramsey error |
Represents the magnitude of the fine error signal on the main (ramsey) peak; <160 nominal. |
+013 |
14 |
Rabi-ramsey error |
Represents the magnitude of the coarse error signal on the main (Rabi) pedestal |
+0012 |
15 |
zeeman error |
Represents the magnitude of the fine error signal on the side (zeeman) peak; <160 nominal. |
+008 |
16 |
Rabi-zeeman error |
Represents the magnitude of the coarse error signal on the side (Rabi) pedestal |
+0036 |
17 |
ocxo control |
Represents the control voltage controlling the ovenized quartz crystal oscillator; ±500 at start of life, ±4900 at end-of-life. |
-1318 |
18 |
Ramsey peak |
Represents the magnitude of the main (Ramsey)
peak; |
2495 |
19 |
C-field control |
Represents the magnitude of the C-field control voltage
|
+0080 |
20 |
zeeman peak |
Represents the magnitude of the first side (zeeman) peak; (Ramsey level - 200 ±200 nominal) |
1677 |
21 |
Ramsey level offset |
Represents the magnitude of the offset voltage added to the Ramsey response to center it within the range of the A/D converter; 60 to 200 nominal, proportional to loop gain factor. |
2 |
22 |
software (numerical) gain |
gain applied to the beam signal, 1 to 5; interacts with the hardware (DAC) gain |
R+Z |
23 |
Ramsey confidence |
confirms central Ramsey symmetry by checking that the difference between adjacent valleys is small, <10 nominal. |
00 |
24 |
microwave power |
represents the magnitude of the microwave power applied to the cesium beam tube |
-0408 |
25 |
+5 V power supply |
voltage (V) |
+5.17 |
26 |
internal temperature |
°C |
+35.5 |
27 |
+15 V power supply |
voltage (V) |
+15.4 |
28 |
-15 V power supply |
voltage (V) |
-15.4 |
29 |
crystal oven state |
F = cold, C = warm |
C |
30 |
cesium oven supply |
voltage (V): 12 during warm-up, approximately 5 quiescent |
04.5 |
31 |
mass spec supply |
voltage (V) of the ionizer filament with respect to ground |
15.5 |
32 |
ionizer supply |
voltage (V) across the ionizer filament |
1.66 |
33 |
C-field supply |
current (mA) through the C-field winding |
17.9 |
34 |
EM HV supply |
voltage (V) applied to the primary of the electron multiplier high voltage supply (-2000 V) |
10.6 |
35 |
IP HV supply |
current (mA) being supplied by the ion pump high voltage supply (+3500 V) |
025 |
36 |
standard deviation |
a measure of the frequency stability of the unit - 90 to 125 for a 12-year tube |
+107 |