Atec Agilent-E8257D - Manual (Page 16)

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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 (Option 1E1) 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)
Video feed-through
3 < 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 +1 V
peak
= RF On +1 V
peak
= RF On
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)
Pulse modulation 1, 2
(Option UNU)
Narrow pulse modulation 1, 2
(Option UNW)