bias-T-dat
What is a Bias-T (DC Injection)?
A Bias-T is a simple circuit that combines:
- DC power (to power a device like an LNA or active antenna)
- RF signal (like from an antenna)
It allows both to travel over the same coaxial cable without interfering with each other.
⚙️ Basic Components
- Inductor (L): Passes DC but blocks RF.
- Capacitor (C): Passes RF but blocks DC.
🔁 How It Works
DC Input ───┬── L ──┬────────────→ To device (DC + RF)
│ │
│ C
▼ │
(Power) └── RF Signal Input- Inductor (L): Injects DC power into the line, while blocking RF from entering the power supply.
- Capacitor (C): Lets RF signal pass through but blocks DC.
📦 Common Uses
- Powering active antennas or LNAs over a single cable.
- Used in satellite dishes, radio receivers, remote sensors.
- Reduces need for extra power wiring.
🧠 Why It’s Useful
- Simplifies installation — just one cable for signal and power.
- Helps power remote or hard-to-reach RF devices.