Frequency Standard
RF-Section:
A22 10 MHz Frequency Standard
Frequency Standard Regulator
The frequency of the internal 10 MHz Frequency Standard is
compared to a known frequency standard and adjusted for minimum
frequency error. This procedure does not adjust the short-term
stability or long-term stability of the 10 MHz Quartz Crystal Oscillator,
which are determined by characteristics of the particular oscillator
and the environmental and warmup conditions to which it has been
recently exposed. The spectrum analyzer must be ON continuously
(not in STANDBY) for at least 72 hours immediately prior to oscillator
adjustment to allow both the temperature and frequency of the
oscillator to stabilize.
with aging
of
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HP 5061B
Frequency Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP
Cables:
BNC cable, 122 cm (48 in)
required) . . . . . . . . . . . . . .
HP 10503A
The spectrum analyzer must be ON continuously (not in STANDBY) for
at least 72 hours immediately prior to oscillator adjustment to allow
both the temperature and frequency of the 10 MHz Quartz Crystal
Oscillator to stabilize. Adjustment should not be attempted before the
oscillator is allowed to reach its specified aging rate. Failure to allow
sufficient stabilization time could result in oscillator misadjustment.
The
10 MHz Quartz Crystal Oscillator (HP P/N 0960-0477)
will typically reach its specified aging rate again within 72 hours
after being switched off for a period of up to 24 hours. If extreme
environmental conditions were encountered during storage or
shipment (i.e. mechanical shock, temperature extremes) the oscillator
could require up to 30 days to achieve its specified aging rate.
1. Set the rear-panel FREQ REFERENCE switch on the spectrum
analyzer RF Section to INT.
The
Vdc STANDBY supply provides power to the heater circuit in
the A22 10 MHz Frequency Standard assembly whenever line power
is applied to the RF Section. This allows the A22 10 MHz Frequency
Standard oven to remain at thermal equilibrium, minimizing
frequency drift due to temperature variations. The OVEN COLD
Adjustments