Radio over Fiber — Dual-antenna emitter box

Two HF antennas,
over a single fiber strand.

The AFB-250 is a dual-antenna Radio-over-Fiber emitter box. It converts two UHF signals (470–800 MHz) picked up by two antennas into a monomode optical signal carried on a single OpticalCon Duo APC cord. Protected antenna remote DC feed, built-in 10 dB attenuator, XLR4 12 V power. Ruggedised for live and fixed-install use. Made in France.

AFB-250

Bandwidth

470 – 800 MHz

Configuration

2 BNC in · 1 fibre duo

DC feed

12 V / 200 mA

Attenuator

0 / −10 dB

Optical output

Neutrik OpticalCon Duo APC

Highlights

Two antennas on one link

Both BNC inputs are modulated on separate wavelengths then multiplexed over a single duo fiber cord: you run one cable where two were required.

2 antennas · 1 duo fiber

Protected DC feed

12 V / 200 mA per input to power active antennas, with short-circuit protection. A faulty antenna doesn't bring down the rest of the chain.

12 V · 200 mA · short-circuit safe

RF Peak indicator

A dedicated LED flags excessive RF field at the input, typically right next to a powerful transmitter. You know when to engage the internal attenuator.

LED RF peak

Built-in 10 dB attenuator

Engaged at start-up: a 10 dB pad that saves the optical stage from saturation in dense RF environments, no external attenuator needed.

0 / −10 dB · internal

Neutrik OpticalCon Duo

Ruggedised optical connector built for the field: mechanical locking, ferrule protection, dust and shock immunity. The reference connector for live events.

OpticalCon Duo · APC 1310 nm

12 V XLR4 power

Standard XLR4, 12 V / 12 W max: compatible with rental battery bricks, broadcast cameras and sound carts. No exotic wall-wart to carry.

XLR4 · 12 V · 12 W max

Specifications

The numbers that matter.

Condensed excerpt. See the datasheet for detailed conditions.

RF

Bandwidth470 – 800 MHz
RF inputs2 × BNC 50 Ω
Internal attenuator0 / −10 dB (activable au démarrage)
RF Peak indicatorLED dédiée
Impedance50 Ω nominal

Fiber & antenna power

Optical outputNeutrik OpticalCon Duo · APC 1310 nm · monomode
Antenna remote feed12 V / 200 mA (protection court-circuit)

Power & mechanical

Power supplyXLR4 · 12 V DC · 12 W max
Idle current500 mA
1 active antenna600 mA
2 active antennas750 mA
Dimensions (L×W×H)155 × 180 × 70 mm
Weight1,3 kg
HousingMétal, conception durcie
ComplianceCE · RoHS · DEEE

Use cases

Live / festival

Route two stage antennas back to the HF control rack

Two antennas in the grid → stage-side AFB-250 → OpticalCon Duo → control-room AFR-200: 150 m of fiber weighs 2.3 kg vs 14 kg of RG213, and the loss is frequency-independent.

Broadcast / event

Cross a hostile EM site without pickup

Stadium, racecourse, industrial site: fiber provides full galvanic isolation between antennas and receiver. No ground loop, no pickup along the run.

Fixed installation

Wire two rooftop antennas to a shooting studio

Rooftop install with AFB-250 in an outdoor IP enclosure; fiber runs into the building and feeds an AFR-200 or ACH-642 in the control room. One-shot cabling for a decade.

Documentation

Everything you need before buying.

Datasheets and user manuals available in PDF format.

Ready to offset your antennas over fiber?

Available by quote, 2–3 weeks delivery.