IFR 2026

GENERAL INFORMATION
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Modulation
FM, AM or phase modulation can be applied to the carriers
generated by each signal source from independent internal or
external modulation sources. The internal modulation sources are
capable of generating two simultaneous signals into any one of the
modulation channels. Each internal and external modulation source
can be enabled simultaneously to produce combined amplitude and
frequency (or phase) modulation. Pulse modulation can be applied
to each of the carriers from external pulse sources. The pulse
modulation can be used in combination with the other forms of
modulation. 2-level or 4-level FSK modulation can be applied to
each carrier using data from an external source.
Frequency modulation
Deviation: 0 to 100 kHz.
Resolution: 3 digits or 1 Hz.
Accuracy: ±5% at 1 kHz modulation rate.
Bandwidth (1 dB): DC to 100 kHz (DC coupled),
10 Hz to 100 kHz (AC coupled),
20 Hz to 100 kHz (AC coupled with ALC).
Group delay:
Less than 5 μs to 100 kHz.
Carrier frequency offset: Less than 1% of the set frequency deviation when DC coupled.
Distortion: Less than 1% at 1 kHz rate for deviations up to 100 kHz,
typically ≤0.3% at 1 kHz rate for deviations up to 10 kHz.
Less than 3% at 1 kHz rate and deviations up to 100 kHz for carrier
frequencies below 50 MHz.
Modulation source: Internal modulation oscillator or external via front-panel BNC.
FSK
Modes:
2-level or 4-level FSK.
Data source:
External data via rear-panel 25-way D-type connector.
Frequency shift: Variable up to ±100 kHz.
Accuracy: As FM deviation accuracy.
Timing jitter:
±3.2 μs.
Filter:
8
th
-order Bessel, −3 dB at 20 kHz.
Phase modulation
Deviation range: 0 to 10 radians.
Resolution: 3 digits or 0.01 radians.
Accuracy at 1 kHz: ±5% of indicated deviation excluding residual phase modulation.
Bandwidth (3 dB): 100 Hz to 10 kHz.
Distortion: Less than 3% at 10 radians at 1 kHz modulation rate. Typically
<0.5% for deviations up to 1 radian at 1 kHz.
Modulation source: Internal LF generator or external via front panel BNC.
Amplitude modulation
Individual outputs For carrier frequencies <500 MHz, usable to 1.5 GHz.
Combined output Unspecified below 5 MHz; usable to 1 MHz. Otherwise as for
individual outputs.
Range: 0 to 99.9%.
Resolution: 0.1%.
Accuracy*: ±5% of set depth at 1 kHz rate, over temperature range 17°C to
27°C.
Temperature coefficient <0.02%/°C.
Bandwidth (1 dB): DC to 30 kHz (DC coupled),
10 Hz to 30 kHz (AC coupled),
20 Hz to 30 kHz (AC coupled with ALC).
Distortion*: <1.5% at 1 kHz rate for modulation depths up to 30%,
<2.5% at 1 kHz rate for modulation depths up to 80%.
Modulation source: Internal LF generator or external via front panel BNC.