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1. With ALC off, specs apply after the execution of power search. Specifications apply with Atten Hold Off (default mode for

instruments with attenuator), or ALC level between –5 and +10 dBm or maximum specific power, whichever is lower.

Above 50 GHz, pulse modulation is useable; however performance is not warranted.

2. Power search is a calibration routine that improves level accuracy with ALC off. The instrument microprocessor momentarily

closes the ALC loop to find the modulator drive setting necessary to make the quiescent RF level equal to an entered value,

then opens the ALC loop while maintaining that modulator drive setting. When executing power search, RF power will

be present for typically 10 to 50 ms; the step attenuator can be set to automatically switch to maximum attenuation to

protect sensitive devices. Power search can be configured to operate either automatically or manually at the carrier frequency,

or over a user-definable frequency range.

3. With attenuator in 0 dB position. Video feed-through decreases with attenuator setting.

500 MHz to 3.2 GHz

Above 3.2 GHz

On/Off ratio

80 dB (typ)

80 dB

Rise/Fall times (Tr, Tf)

100 ns (typ)

6 ns (typ)

Minimum pulse width

Internally leveled

2 us

1 us

Level hold (ALC off with power search) 0.5 us

0.15 us

Repetition frequency

Internally leveled

10 Hz to 250 kHz

10 Hz to 500 kHz

Level hold (ALC off with power search) dc to 1 MHz

dc to 3 MHz

Level accuracy (relative to CW)

Internally leveled

±0.5 dB

±0.5 dB

Level hold (ALC off with power search) ±0.5 dB (typ)

±0.5 dB (typ)

Width compression

±50 ns (typ)

±5 ns (typ)

(RF width relative to video out)

< 200 mv (typ)

< 2 mv (typ)

Video delay (ext input to video)

50 ns (nom)

50 ns (nom)

RF delay (video to RF output)

270 ns (nom)

35 ns (nom)

Pulse overshoot

< 10% (typ)

< 10% (typ)

Input level

Input impedance

50

Ω (nom)

50

Ω (nom)

10 MHz to 3.2 GHz

Above 3.2 GHz

On/Off ratio

80 dB

80 dB

Rise/Fall times (Tr, Tf)

10 ns (8 ns typical)

10 ns (6 ns typical)

Minimum pulse width

Internally leveled

1 us

1 us

Level hold (ALC off with power search) 20 ns

20 ns

Repetition frequency

Internally leveled

10 Hz to 500 kHz

10 Hz to 500 kHz

Level hold (ALC off with power search) dc to 5 MHz

dc to 10 MHz

Level accuracy (relative to CW)

Internally leveled

±0.5 dB

±0.5 dB (0.15 dB typical)

Level hold (ALC off with power search) ±1.3 dB (typ)

±0.5 dB (typ)

(Option UNW)