1. The Golden Rule: Polarization

Think of polarization like a "key" and a "lock." If your drone is sending a signal spinning one way, and your goggles are looking for a signal spinning the other, they won't fit.

LHCP

Left-Hand Circular Polarization. Standard for Digital systems (DJI, Walksnail).

RHCP

Right-Hand Circular Polarization. The classic standard for Analog FPV.

⚠️ CRITICAL: Mismatching LHCP and RHCP results in a -20dB signal loss. That is a 99% reduction in range. Check your labels!

2. Beam Patterns (Omni vs Patch)

Omnidirectional (The Lightbulb)

Sends and receives signal in a 360° "donut" shape. Essential on the drone because the quad is constantly flipping and turning. Great for close-range flying all around yourself.

+ Coverage everywhere
- Lower overall range

Patch / Directional (The Flashlight)

Focuses all its "listening" power in one direction. To use these, you must keep your head pointed toward the drone. Essential for long-range or flying behind objects.

+ Massive range depth
- Zero signal behind you

3. Physical Connectors

Type	Best Use Case
SMA	Standard for goggles and large 5-inch drones. Threaded with a pin in the middle.
RP-SMA	Reverse Polarity. The 'hole' and 'pin' are swapped. Common in older WiFi gear and some FPV brands.
U.FL / IPEX	Micro connectors found directly on VTX boards. Extremely fragile; only rated for a few 'clicks'.
MMCX	The middle ground. Sturdier than U.FL, smaller than SMA. Great for racing drones.