Analog FPV system remains to be broadly used resulting from their low latency and affordability, however they are often stricken by varied video points—like rolling photos, noise strains, or interference. On this information, I’ll share tips on how to troubleshoot and repair these analog FPV video issues based mostly on finest practices and real-world expertise.
Powering VTX and Digicam
In case your video feed turns into noisier once you throttle up, it’s possible resulting from electrical noise from the battery reaching your digicam or VTX. That is usually attributable to voltage fluctuations or poor filtering. Finest Apply is to energy your FPV digicam and VTX from a BEC (regulated output) on the flight controller, indirectly from the LiPo. FPV units choose secure voltage to transmit clear indicators.
Add Capacitors to the ESC Energy Pads
Even with onboard filtering, further capacitors can assist suppress voltage spikes and ripples, and clear up energy to the flight controller and video system.
Advice: Solder a low-ESR capacitor to your ESC energy pads (XT60/XT30 enter aspect). That is particularly efficient for filtering motor-induced noise. Extra information: Why You Ought to Add a Capacitor – https://oscarliang.com/capacitors-mini-quad/
If noise persists, contemplate including small capacitors (e.g. 470μF) to the 5V or 12V rails, although that is not often wanted.
Twist Sign and Floor Wires
Twisting your video sign and floor wires collectively helps reject electromagnetic interference. This works by making a pure defend towards noise from ESCs or BECs. Additionally, maintain video sign and energy wires away from inductors or energy provide elements on the board.
Protect the ESC from the Flight Controller
MOSFETs on ESCs can generate interference affecting your FC’s BEC. Some ESCs embody a metallic defend because of this. If yours doesn’t, you would possibly contemplate including EMI shielding materials or changing it with a shielded ESC.
Correct Grounding is Essential
Your circuit is incomplete with no strong floor connection. In the event you energy your digicam and VTX individually however don’t join sign floor, the sign turns into extra weak to energy noise.
Suggestions: Join digicam and VTX grounds to the identical floor pad (or at the very least pads shut collectively).
That is particularly essential if powering the video system instantly from the LiPo.
Diagnosing White Traces in Video
White horizontal strains usually point out extreme electrical noise, particularly within the digicam or VTX energy. Fixes embody:
- Including a low-ESR capacitor to the XT60 pads
- Powering the digicam from the VTX, which frequently gives higher regulated energy
- Utilizing a filtered BEC output
Diagnosing Black Traces in Video
Black flickering strains usually imply your VTX isn’t receiving sufficient energy. That is widespread at larger output energy ranges.
Options:
- Energy the VTX instantly from the battery
- Guarantee your BEC’s present ranking is excessive sufficient
- If points persist, strive one other VTX or digicam
Bonus Tip: Test that motor screws aren’t too lengthy—they might be shorting towards motor windings. Right here’s tips on how to verify: https://oscarliang.com/check-motor-screws-touching-winding/
Test Your Antennas
Not all video points are power-related—dangerous or mismatched antennas are a standard reason for poor picture high quality.
- Guarantee each VTX and goggles have matching connectors (SMA / RP-SMA)
- Match round polarization (RHCP / LHCP)
- Attempt altering video channels if there’s potential for interference
Flying With Others?
In the event you’re flying with a bunch and experiencing interference, be sure you’re on non-overlapping channels. Right here’s a information to choosing the very best analog channels: https://oscarliang.com/fpv-channels/
Jello in FPV Video
In case your quad is tuned effectively and also you’re nonetheless seeing jello, it’s possible a mechanical challenge. Fashionable FPV cameras use CMOS sensors, that are extra liable to vibration artifacts than CCD sensors.
Test for:
- Unfastened digicam mount screws
- Unfastened or cracked digicam lens lock nuts
- Unfastened digicam sensor contained in the housing
If all else fails, strive utilizing TPU digicam mounts to dampen vibrations.
Fixing Vertical Video Rolling
Analog FPV video is made up of frames, and every body consists of many scan strains. To show every body correctly, the system makes use of a sync pulse on the finish of each body to inform the receiver when the following body is coming.
If the receiver loses the sync pulse, it not is aware of the place the highest of the display is—leading to your picture rolling vertically. Even when the picture knowledge is generally nice, a lacking or inconsistent sync pulse can throw off your entire show.
To repair this challenge, some superior video receivers use sync pulse reconstruction. Modules just like the ImmersionRC Rapidfire and TBS Fusion, have sync pulse reconstruction operate when sync pulse is misplaced. This retains your picture from rolling, even with a weak or noisy sign.
Need assistance to determine which module to purchase? Right here’s my Fusion vs Rapidfire Comparability: https://oscarliang.com/rapidfire-fusion/
Fixing Video Scrolling Sideways
Some superior video receiver modules have sync pulse reconstruction funcitons as mentioned above, this addresses the video rolling points when you may have weak or noisy sign the place sync pulse is misplaced.
Nonetheless, this function assumes the digicam is sending sync pulses that conform to plain NTSC or PAL timing. Sadly, some low high quality FPV cameras don’t comply with these requirements carefully, they usually would possibly generate sync pulses which are inconsistent or exterior the anticipated timing vary. This confuses the receiver module’s sync reconstruction algorithm. As a substitute of serving to, it finally ends up injecting pretend sync pulses on the flawed time—resulting in the sideways scrolling challenge.
To verify if that is the problem you’re having, strive swapping to a different analog digicam (totally different model or mannequin). If the problem goes away, it’s possible your unique digicam is producing unstable sync pulses.
If in case you have Rapidfire or TBS Fusion, strive disabling sync pulse reconstruction function, or switching to a unique mode. These are normally listed beneath totally different variety or video modes:
- Rapidfire: Mode 1 / 2 / Legacy
- Skyzone: Variety Combine 1, 2, or 3
Disabling sync reconstruction might repair the scrolling challenge—nevertheless it removes a serious function that improves analog video in weak sign circumstances. It’s possible you’ll now expertise flickering or tearing when sign high quality drops. To essentially handle the problem it could be price getting a greater digicam as an alternative.
Closing Ideas
Analog FPV programs are nonetheless in style, however they require correct setup and upkeep for the very best efficiency. Begin with clear energy, correct grounding, and suitable antennas, then transfer on to digicam high quality and receiver settings.
With some easy diagnostics and fixes, you may vastly enhance your analog video expertise—and remove a lot of the irritating picture artifacts that analog pilots encounter.
Edit Historical past
- Mar 2018 – Article created
- Apr 2019 – Up to date
- Jul 2019 – added “the place so as to add cap” and “twisting sign/floor wires”
- Sep 2019 – added information about “ESC shielding” and matching antennas
- Dec 2019 – Revised
- Could 2025 – Revised
