For example: Agilent E4440A or Anritsu 68369
AC Power Supplies
Programmable AC Power Sources, Frequency Converters
Xantrex CW801M
AC Power Source, 800 VA, 1Ø, 135/270 VAC, 45 - 500 Hz (1 KHz optional)

Manufacturer: Xantrex
Xantrex CW801P
CW801P 800 VA, ContinuousWave AC Power Source - Programmable - CW Series

Manufacturer: Xantrex
California Instruments-Ametek FCS18M
AC Power Source 18kVA

Manufacturer: California Instruments-Ametek
California Instruments-Ametek FCS18P-PT
AC Power Source 18KVA

Manufacturer: California Instruments-Ametek
California Instruments-Ametek FCS36M
AC Power Source 36 kVA

Manufacturer: California Instruments-Ametek
California Instruments-Ametek FCS36P-PT
AC Power Source 36 kVA

Manufacturer: California Instruments-Ametek
California Instruments-Ametek FCS54M
AC Power Source 54kVA

Manufacturer: California Instruments-Ametek
California Instruments-Ametek FCS54P-PT
AC Power Source 54kVA

Manufacturer: California Instruments-Ametek
California Instruments P
Standard Programmable Type-P Controller

Manufacturer: California Instruments
California Instruments PT
Transient Programmable Type-PT Controller

Manufacturer: California Instruments
Steelman Industries, Inc. R-3/6-230-LD
Rotary Phase Conversion Converter Systems

Manufacturer: Steelman Industries, Inc.
Ametek - Elgar SGA 60X 250C-0AAA
Programmable Precision DC Power Supply

Manufacturer: Ametek - Elgar