Atec Fluke-910-910R - Manual (Page 3)

be selected manually by activat-
ing the Manual Hold-Over Key. If
Manual hold-over is set together
with a valid received GPS signal,
the actual frequency offset is
calculated, displayed and stored
in non-volatile memory every
24-hours.
For the ultra-stable rubidium
oscillator in the 910R, there
is no measurable difference
between the stability in disci-
plined and hold-over mode, for
averaging times up to 1000 s.
Designed for portability too
When using manual hold-over
mode, the 910 or 910R act as a
stand-alone OCXO or rubidium
frequency standard. This means
that one typical drawback of
a GPS receiver, lack of porta-
bility, is eliminated. A typical
GPS receiver needs hours to
lock after a change of location,
whereas the 910 and 910R are
up and running after just ten
minutes.
GPSView Software
GPSView is a Windows
95/98/2000/NT program that
communicates with the GPS-
controlled frequency standard.
Its main purpose is to provide a
traceable calibration document
based on the 24-hour frequency
offset values, internally stored
in the non-volatile memory of
model 910/910R (Figure 3).
It is only necessary to
download data to a PC to the
910/910R once every second
year to obtain an unbroken
traceability chain since first use.
For performance analysis over a
shorter period and for short-term
phase variation, data can be
obtained over the latest forty-
day period.
From GPSView, the user can
control the operating mode (Dis-
ciplined or Hold-Over), and lock
the front panel to prevent unin-
tended change via the Manual
Hold-Over Key. The user can also
set the optional pulse output
frequency and duty cycle.
Figure 3. GPSView can print a calibration protocol at any time.
910R (GPS-Rb)
Frequency stability -
locked to GPS
Frequency offset (24h mean):
< 1 x 10 -12 *
Short term (Allan dev.):
< 1 x 10 -12 (τ = 1000 s)
< 3 x 10 -12 (τ = 100 s)
< 1 x 10 -11 (τ = 10 s)
< 3 x 10 -11 (τ = 1 s)
Warm up (+25 °C): 20 mins to lock
*At temperature 23 °C ± 3 °C
Frequency stability -
Hold-Over
Aging/24h: < 2 x 10 -12 (typ.)
Aging/month: < 5 x 10 -11
Temp. (0 °C to + 50 °C): < 3 x 10 -10
Temp. (23 °C ± 3 °C): < 2 x 10 -11 (typ.)
Short term (Allan dev.):
< 3 x 10 -12 (τ = 100 s)
< 1 x 10 -11 (τ = 10 s)
< 3 x 10 -11 (τ = 1 s)
Warm up (+25 °C): 10 minutes to 4 x 10 -10
Phase noise
Offset Phase noise
1 Hz -80 dBc/Hz (typ.)
10 Hz -90 dBc/Hz (typ.)
100 Hz -130 dBc/Hz (typ.)
1 kHz -140 dBc/Hz (typ.)
10 kHz -140 dBc/Hz (typ.)
100 kHz -145 dBc/Hz (typ.)
910 (GPS-OCXO)
Frequency stability -
locked to GPS
*Frequency offset (24h mean):
< 2 x 10 -12
Short term (Allan dev.):
< 5 x 10 -11 (τ = 1000 s)
< 3 x 10 -11 (τ = 100 s)
< 5 x 10 -12 (τ = 10 s)
< 5 x 10 -12 (τ = 1 s)
Warm up (+25 °C): 20 mins to lock
*At temperature 23 °C ± 3 °C
Frequency stability -
Hold-Over
Aging/24h: < 3 x 10 -10
Aging/month: < 3 x 10 -9
Temp. (0 °C to +50 °C): < 2.5 x 10 -9
Temp. (23 °C ± 3 °C): < 4 x 10 -10 (typ.)
Short term (Allan dev.):
< 1 x 10
-11 (τ = 100 s)
< 5 x 10 -12 (τ = 10 s)
< 5 x 10 -12 (τ = 1 s)
Warm up (+25 °C): 10 minutes to 5 x 10 -9
Phase noise
Offset Phase noise
1 Hz -100 dBc/Hz (typ.)
10 Hz -120 dBc/Hz (typ.)
100 Hz -130 dBc/Hz (typ.)
1 kHz -135 dBc/Hz (typ.)
10 kHz -135 dBc/Hz (typ.)
100 kHz -135 dBc/Hz (typ.)
910/910R specifications
3 Fluke Calibration 910/910R GPS Controlled Frequency Standards