For example: Agilent E4440A or Anritsu 68369
Tektronix Function Generators
Tektronix AWG2021
Tektronix AWG2021 3 Ch. Arbitrary Waveform Generator, 125 MHz, 250 MS/s
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Manufacturer: Tektronix
Tektronix AWG7102
10GS/s, 2ch, 10bits, 32M point/ch Arbitrary Waveform Generator
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Manufacturer: Tektronix
Tektronix AWG710B
Tektronix AWG710B 4.2GS/s 1CH Arbitrary Waveform Generator Arbitrary Waveform Generator
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Manufacturer: Tektronix
Tektronix AWG7121B
12GS/s, 1ch, 10bits, 32M point/ch Arbitrary Waveform Generator
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Manufacturer: Tektronix