Analog vs. digital

FPV drones use either analog or a digital video transmission system. It’s important to note that whichever you choose, no consumer drone has protections against somebody else watching the feed if they know the channel you’re on. The key things about picking your video mode are compatibility, latency, and video quality.

Goggles typically support a single mode, except for a few that support both analog and one of the digital modes. I don’t know of any that support multiple digital modes. If you already have goggles, this is will influence your drone choice; if you’re buying new, you have to decide which ecosystem to buy into.

Latency is also important: it’s the lag between what the drone sees and when you see it. Analog sets the baseline at roughly 17ms of latency. If you’re maneuvering quickly or in confined spaces, lower latency is preferred.

Analog has a lower quality than the digital modes, which are all HD now. This comes up in both maneuvering (you might not see obstacles until you get right up on them) and PID. An ISR drone might have a harder time picking out details with a lower quality video system.

A note on video power: in the US, legally you’d need an amateur radio license to go more than 1W. On whoops, you probably will see at most 400mW so this is probably not going to be a concern until you get to bigger quads.

Multipath

When you have multiple return paths for the video signal, such as in a valley or a building, it can do weird things with your video. Some digital modes handle this better than others; analog will generally see rolling or ghosted images (where two video signals are overlaid).

Analog

Analog is what I fly the most; I prefer the way it degrades more gracefully than digital modes, and it has a lower latency. I don’t generally find the image quality an issue. In an environment with a lot of multipath support, the better degradation usually means you can limp out of the situation. Here’s an example where I lost the video transmitter (VTX) on a drone (a previous crash ripped off the antenna, and I didn’t notice).

Note that analog also allows you to use more power, up to 2.5W (though you’ll need an amateur radio license to do this legally).

HDZero

HDZero is what I think is the closest digital mode to analog (it sometimes gets called “analog plus”). It has a pretty low latency accordingly; you can drop the size to 540p and get even better latency than analog. In 1080p30 mode, latency is roughly 33ms. I use HDZero as my digital system and I find it works pretty okay, though I prefer analog. However, it does have better image quality.

DJI

This is a proprietary system and you’ll need to buy DJI’s goggles for this; however, this is the highest quality digital system on all factors except your wallet. As best as I can tell, you won’t be able to buy upgrades, but the O4 video transmitter and DJI Goggles 3 can still be bought. New parts and replacements may be more difficult to get. Caveat emptor: I don’t own any DJI FPV gear.

BetaFPV Artlynk

I had a drone using this. It wasn’t spectacular, and only BetaFPV makes them. I ended up swapping out the VTX for an HDZero VTX. I wouldn’t use it.

Walksnail Avatar

This is another digital system. I’ve heard decent reviews, but I’ve never flown or used these so I can’t provide any advice on it.