VBA0742 Series — 0.7 to 4.2 GHz Class-A RF Power Amplifiers

Broadband, mismatch-tolerant RF power for radiated immunity, stripline, and antenna drive
Vectawave’s VBA0742 Series covers 0.7–4.2 GHz with true Class-A linearity based on GaN wideband output stages and Vectawave’s quadrature-hybrid combiners. The result is low distortion, high reliability, and unconditional operation into severe mismatch—ideal for IEC/EN 61000-4-3 radiated immunity (stripline/small antennas), DO-160 §20 work, and demanding chamber applications.

Key Technical Advantages

• Class-A architecture for the lowest distortion in EMC immunity; designed to maintain output without fold-back under high reflection.
• GaN push-pull wideband stages with proprietary quadrature-hybrid combining for efficient, rugged output over 0.7 - 4.2 GHz. 
• 700 MHz - 4.2 GHz instantaneous bandwidth for stripline, small antenna drive, and chamber field generation. 
• Unconditional stability & ∞:1 output VSWR tolerance (any phase) on series models, supporting variable fixtures/antennas.
• Modern remote interfaces (Ethernet/USB/GPIB) with front-panel control for enable/monitoring/interlocks.

Models & Core Specifications 

Specification	VBA0742-18	VBA0742-30	VBA0742-50	VBA0742-70	VBA0742-130	VBA0742-250
Picture
Typ. Performance Curve
Frequency Range	0.7-4.2 GHz	0.7-4.2 GHz	0.7-4.2 GHz	0.7-4.2 GHz	0.7-4.2 GHz	0.7-4.2 GHz
Type	Class-A; GaN, quadrature combiner	Class-A; GaN, quadrature combiner	Class-A; GaN, quadrature combiner	Class-A; GaN, quadrature combiner	Class-A; GaN, quadrature combiner	Class-A; GaN, quadrature combiner
Output VSWR Tolerance	∞:1, 100 % mismatch tolerant	∞:1, 100 % mismatch tolerant	∞:1, 100 % mismatch tolerant	∞:1, 100 % mismatch tolerant	∞:1, 100 % mismatch tolerant	∞:1, 100 % mismatch tolerant
Rated / Typical Power	CW ≥18W, P1dB ≥12W	CW ≥30 W, P1dB ≥22W	CW ≥50 W, P1dB ≥35W	CW ≥70W, P1dB ≥60W	CW ≥130W, P1dB ≥110W	CW ≥1–4.2GHz 250W 4.2–6GHz 200W, P1dB ≥1–4.2MHz 200W 4.2–6MHz 150W
Gain (min)	43dB	46 dB	47 dB	49 dB	51 dB	54 dB
Gain Flatness	±3 dB	±3 dB	±3 dB	±3 dB	±3 dB	±3 dB
TOI (typ)	51 dBm	54 dBm	56 dBm	58 dBm	60 dBm	64 dBm
Harmonics @ Linear Power	< –20 dBc	< –20 dBc	< –20 dBc	< –20 dBc	< –20 dBc	< –20 dBc
RF Input / Output Connectors	Type N (f)	Type N (f)	Type N (f)	Type N (f)	Type N (f)	Type N (f)
Input Power (Mains)	100-240V ac 45-63Hz, 150VA  IEC320-C14	100-240V ac 47-63Hz, <300kVA  IEC320-C14	100-240V ac 47-63Hz, <450kVA  IEC320-C14	100-240V ac 45-63Hz, <1.5kVA  IEC320-C20	100-240V ac 45-63Hz, <2kVA  IEC320-C20	100-240Vac 45-63Hz, <3kVA IEC320-C20
Size & Weight	19-inch, 3U Case, 500mm Deep, 6kg	19-inch, 3U Case, 500mm Deep, 7kg	19-inch, 3U Case, 500mm Deep, 12kg	19-inch, 4U Case, 600mm Deep, 15kg	19-inch, 4U Case, 600mm Deep, 20kg	19-inch, 7U case, 600mm Deep, 40kg
Interface	USB/GPIB control; front panel display	USB/GPIB control; front panel display	USB/GPIB control; front panel display	USB/GPIB control; front panel display	USB/GPIB control; front panel display	USB/GPIB control; front panel display
Notes	Front or Rear connectors	Front or Rear connectors	Front or Rear connectors	Rear connectors	Rear connectors	Rear connectors

EMC Applications & Standards Coverage

• Radiated RF Immunity: IEC/EN 61000-4-3 (stripline/small antennas, chamber drive). 
• Automotive testing for ASLE and Reverb
• Avionics Susceptibility: RTCA/DO-160 §20 (radiated/conducted—upper-band amplifier drive).
• General EMC/chamber use: field generation, transducer/fixture drive over 1–6 GHz.

Control, Monitoring & Protection (Model-Dependent)

• Local front-panel control with Ethernet/USB/GPIB remote interfaces for enable, metering, and interlocks. 
• Designed for continuous duty into high VSWR loads; unconditional stability specified on models like VBA0742-50.

Why Absolute EMC

Absolute EMC sizes amplifiers to your field targets and integrates directional couplers/power meters, striplines/antennas, safety interlocks, and monitoring—so your system hits levels with margin from 0.7 GHz to 4.2 GHz on day one.

What to Specify (Selection Guide)

1. Test method & field level (e.g., IEC 61000-4-3 10/20/30 V/m; DO-160 §20).

2. Fixture/antenna & insertion loss (stripline, log-periodic, biconical, horn).

3. Required linear output (P1 dB) at 0.7 GHz and 4.2 GHz with margin.

4. Mains power & remote interface needs (Ethernet/USB/GPIB).

5. Rack space & connectorization preferences.

Typical System Block

Signal source / RF generator → leveling & power meter/coupler → VBA 0742 amplifier → stripline/antenna → EUT, with reverse-power/VSWR monitoring and interlocks. ∞:1 VSWR tolerance & unconditional stability simplify integration with variable antennas/fixtures.

Frequently Asked Questions

Q1. Will the amplifier tolerate severe mismatch from my antenna or stripline?
Yes. VBA 0742 models are designed for EMC with Class-A operation and ∞:1 VSWR tolerance; VBA0742-70 explicitly specifies unconditional stability and ∞:1 any phase. 

Q2. Should I size to rated (P3 dB) or linear (P1 dB) power?
For immunity targets, size to P1 dB at 4.2 GHz with fixture/antenna loss margin; use rated power only for headline comparison. (See model datasheets for curves.) 

Q3. Can I remote-control these amplifiers?
Yes—Ethernet/USB/GPIB interfaces are provided for enable, metering, and health/interlocks.

Ordering Information

• Models: VBA0742-18, -30, -50, -70, -130, -250 (0.7–4.2 GHz). 
• Included: Amplifier, mains cable, user manual.
• Options/Accessories: Directional couplers & power meters, striplines/antennas, field probes, control/monitoring packages.
• Warranty & Support: Absolute EMC commissioning assistance and application support.