Warm Up Time (Standard Time Base):
From Standby:
30 minutes.
From Cold Start (0
°
C):
120 hours to achieve <2 x 10
–8
per day frequency stability.
Warm Up Time (Option 16 Time Base):
From Standby:
30 minutes
From Cold Start (0
°
C):
72 hours to achieve <5 x 10
–10
per day frequency stability.
Power:
90-132 Vac or 180-264 Vac, 48–440 Hz, 400 VA maxi-
mum
Standby: With ac line power connected, unit is placed in
standby when front panel power switch is released from the
OPERATE position.
Weight: 23 kg (50 lb) maximum
Dimensions:
133 H x 429 W x 597 D mm
(5.25 H x 16.875 W x 23.5 D in)
RF Output Connector:
Type K female,
≤
40 GHz models
Type V female,
≤
50 GHz models.
ENVIRONMENTAL
Storage Temperature Range: –40
°
C to +75
°
C.
Operating Temperature Range: 0
°
C to +50
°
C.
Relative Humidity: 5% to 95% at 40
°
C.
Altitude: 4,600 meters (15,000 ft), 17.3" Hg.
EMI: Meets the conducted and radiated emission require-
ments of:
EN55011/1991 Class A/CISPR-11 Class A
EN50082-1/1992
IEC 801-2/1991 4 kV CD, 8 kV AD
IEC 801-3/1984 3 V/m (26-1000 MHz)
IEC 801-4/1988 500V DC and I/O; 1000V AC
MIL-STD-461C Part2 RE01, RE02, CE01, CE03,
CS01, CS02, CS06, RS03
INPUTS and OUTPUTS
AM IN : Accepts an external signal to AM modulate the RF
output signal. Front or rear-panel input, 50
Ω
or 600
Ω
imped-
ance, both selectable from front-panel modulation menu.
FM IN : Accepts an external signal to FM modulate the RF
output signal. Front or rear-panel input, 50
Ω
or 600
Ω
imped-
ance, both selectable from front-panel modulation menu.
IN : Accepts an external TTL compatible signal to
pulse modulate the RF output signal. Front or rear-panel
input, selectable from front-panel modulation menu.
EXT ALC IN (External ALC Input): Provides for leveling
the RF output signal externally with either a detector or power
meter. Signal requirements are shown in the RF Output
specifications on page B-4.
RF OUTPUT: Provides for RF output from 50
Ω
source im-
pedance. K or V Connector, female. Option 9 moves the RF
Output connector to the rear panel.
10 MHz REF IN: Accepts an external 10 MHz
±
100 Hz,
0 to +10 dBm time-base signal. Automatically disconnects
the internal high-stability time-base option, if installed. 50
Ω
impedance.
10 MHz REF OUT: Provides a 0.5 Vp-p, AC coupled,
10 MHz signal derived from the internal frequency standard.
50
Ω
impedance.
Input/Output Connectors
Nomenclature
Type
Location
AM IN
BNC
Front & Rear Panel
FM IN
BNC
Front & Rear Panel
IN
BNC
Front & Rear Panel
EXT ALC IN
BNC
Front & Rear Panel
RF OUTPUT
K-Connector
V-Connector
Standard-Front Panel
Option 9-Rear Panel
10 MHz REF IN
BNC
Rear Panel
10 MHz REF OUT
BNC
Rear Panel
HORIZ OUT
BNC
Rear Panel
MARKER OUT
BNC
Rear Panel
PEN LIFT OUT
BNC
Rear Panel
RETRACE
BLANK OUT
BNC
Rear Panel
SEQ SYNC OUT
BNC
Rear Panel
DWELL IN
BNC
Rear Panel
V/GHz OUT
BNC
Rear Panel
AUX I/O
25-pin D-type
Rear Panel
SERIAL I/O
RJ45
Rear Panel
IEEE-488 GPIB
Type 57
Rear Panel
PERFORMANCE
SPECIFICATIONS
681XXB OM
B-7