Analog FPV system continues to be extensively used because of their low latency and affordability, however they are often affected by numerous video points—like rolling pictures, noise strains, or interference. On this information, I’ll share the right way to troubleshoot and repair these analog FPV video issues based mostly on greatest practices and real-world expertise.
Powering VTX and Digital camera
In case your video feed turns into noisier if you throttle up, it’s seemingly because of electrical noise from the battery reaching your digital camera or VTX. That is usually attributable to voltage fluctuations or poor filtering. Finest Follow is to energy your FPV digital camera and VTX from a BEC (regulated output) on the flight controller, indirectly from the LiPo. FPV units desire secure voltage to transmit clear indicators.
Add Capacitors to the ESC Energy Pads
Even with onboard filtering, further capacitors may also help 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 facet). That is particularly efficient for filtering motor-induced noise. Extra data: Why You Ought to Add a Capacitor – https://oscarliang.com/capacitors-mini-quad/
If noise persists, think about including small capacitors (e.g. 470μF) to the 5V or 12V rails, although that is hardly ever wanted.
Twist Sign and Floor Wires
Twisting your video sign and floor wires collectively helps reject electromagnetic interference. This works by making a pure protect in opposition to noise from ESCs or BECs. Additionally, preserve video sign and energy wires away from inductors or energy provide parts on the board.
Protect the ESC from the Flight Controller
MOSFETs on ESCs can generate interference affecting your FC’s BEC. Some ESCs embrace a steel protect for that reason. If yours doesn’t, you may think about including EMI shielding materials or changing it with a shielded ESC.
Correct Grounding is Essential
Your circuit is incomplete with out a stable floor connection. If you happen to energy your digital camera and VTX individually however don’t join sign floor, the sign turns into extra weak to energy noise.
Ideas: Join digital camera and VTX grounds to the identical floor pad (or at the very least pads shut collectively).
That is particularly vital if powering the video system straight from the LiPo.
Diagnosing White Strains in Video
White horizontal strains usually point out extreme electrical noise, particularly within the digital camera or VTX energy. Fixes embrace:
- Including a low-ESR capacitor to the XT60 pads
- Powering the digital camera from the VTX, which frequently affords higher regulated energy
- Utilizing a filtered BEC output
Diagnosing Black Strains in Video
Black flickering strains usually imply your VTX isn’t receiving sufficient energy. That is frequent at increased output energy ranges.
Options:
- Energy the VTX straight from the battery
- Guarantee your BEC’s present score is excessive sufficient
- If points persist, strive one other VTX or digital camera
Bonus Tip: Examine that motor screws aren’t too lengthy—they could possibly be shorting in opposition to motor windings. Right here’s the right way to test: https://oscarliang.com/check-motor-screws-touching-winding/
Examine 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)
- Strive altering video channels if there’s potential for interference
Flying With Others?
If you happen to’re flying with a gaggle and experiencing interference, ensure you’re on non-overlapping channels. Right here’s a information to selecting 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 seemingly a mechanical situation. Trendy FPV cameras use CMOS sensors, that are extra vulnerable to vibration artifacts than CCD sensors.
Examine for:
- Unfastened digital camera mount screws
- Unfastened or cracked digital camera lens lock nuts
- Unfastened digital camera sensor contained in the housing
If all else fails, strive utilizing TPU digital camera 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 subsequent 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 usually wonderful, a lacking or inconsistent sync pulse can throw off your entire show.
To repair this situation, some superior video receivers use sync pulse reconstruction. Modules just like the ImmersionRC Rapidfire and TBS Fusion, have sync pulse reconstruction perform 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 will have weak or noisy sign the place sync pulse is misplaced.
Nonetheless, this characteristic assumes the digital camera is sending sync pulses that conform to straightforward NTSC or PAL timing. Sadly, some low high quality FPV cameras don’t comply with these requirements carefully, and so they may generate sync pulses which are inconsistent or exterior the anticipated timing vary. This confuses the receiver module’s sync reconstruction algorithm. As an alternative of serving to, it finally ends up injecting faux sync pulses on the incorrect time—resulting in the sideways scrolling situation.
To test if that is the problem you might be having, strive swapping to a different analog digital camera (completely different model or mannequin). If the problem goes away, it’s seemingly your authentic digital camera is producing unstable sync pulses.
If in case you have Rapidfire or TBS Fusion, strive disabling sync pulse reconstruction characteristic, or switching to a unique mode. These are often listed below completely different variety or video modes:
- Rapidfire: Mode 1 / 2 / Legacy
- Skyzone: Range Combine 1, 2, or 3
Disabling sync reconstruction could repair the scrolling situation—but it surely removes a significant characteristic that improves analog video in weak sign circumstances. It’s possible you’ll now expertise flickering or tearing when sign high quality drops. To actually tackle the problem it may be value getting a greater digital camera as a substitute.
Last Ideas
Analog FPV programs are nonetheless well-liked, 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 digital camera high quality and receiver settings.
With some easy diagnostics and fixes, you possibly can vastly enhance your analog video expertise—and eradicate many 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 data about “ESC shielding” and matching antennas
- Dec 2019 – Revised
- Could 2025 – Revised