Digital Video Transmission System Decision Matrix

	Notes	OpenHD	DJI O3	HDZero	Walksnail

	Notes	OpenHD	DJI O3	HDZero	Walksnail
URL to product		https://openhd.gitbook.io/open-hd/	https://www.dji.com/ca/o3-air-unit	Whoop Lite (W): https://www.hd-zero.com/product-page/hdzero-whoop-lite-vtx Race V3 (R): https://www.hd-zero.com/product-page/hdzero-race-v3-vtx	https://caddxfpv.com/products/walksnail-avatar-vrx?variant=43697052418350
Description		Is a software that uses wifi adapters to transmit data. Can be used on Raspberry Pi	Full commercial product designed for use with their own product lines (FPV goggles) Known to produce lots of heat	HDZero is a brand, has many products available	Product comes in various combination of bundles
Range	Higher is better	Depends on wifi adapter: ~3km for low power adapters, 75km record with 30dbi antenna	10km	7km (4-5 km is pretty clear, 7km gets a lot of static)	4km
Size (WxLxH) [air]	Lower is better	Depends on wifi adapter	VTX: 32.5×30.5×14.5 mm antenna: 85 mm 25.5 x 25.5mm M1.6 mounting	W: 32.4 x 32.5 x 4 mm (29x29mm inner) (25.5 x 25.5mm M2 mounting) R: 32mm x 28mm x 5mm (20mm x 20mm M4 mounting)	33 x 33 x 9.5 mm 25.5 x 25.5 mm mounting
Mass [air]	Lower is better	Depends on wifi adapter	28g (transmitter) + 3g (antenna) = 31g	W: 4.5g (without shield) R: 5.5g (without shield)	16g
Latency	Lower is better	On a Raspberry Pi, >100ms “glass to glass”	30ms @1080p/100fps 40ms @1080p/60fps	W: unknown R: 14ms @540p/90fps	22ms average
Transmitter (VTX) [air]		8812AU or 8812BU WiFi Card	Cannot purchase separately	W and R	https://caddxfpv.com/collections/walksnail-avatar-system/products/walksnail-avatar-hd-vtx-only $100 on its own
Receiver (VRX) [ground]		8812AU or 8812BU WiFi Card	DJI goggles 2, FPV goggles V2 Others are unknown	https://www.hd-zero.com/product-page/hdzero-vrx Note: need to buy SMA antennas Others are unknown	$220 on its own Has a MicroSD card slot for DVR (supports up to 256GB micro SD cards)
Camera support		https://openhd.gitbook.io/open-hd/hardware/cameras Should support a lot of them	Comes with a camera Other camera support unknown	Does come with a camera if choose to buy a bundle (like $30 more) Other camera support unknown	Does come with a camera if choose to buy a bundle Other camera support unknown
Operating frequency		all 2.4 and 5.8 GHz bands	2.400-2.4835 GHz (RX only) 5.725-5.850 GHz (RX and TX)	W: 5.8 GHz R: 5.8 GHz	5.725-5.850 GHz
Output		Video: unknown https://play.google.com/store/apps/details?id=com.openhd.openhd MAVLink Telemetry Support	With DJI Goggles 2: 4K@30/50/60/100/120fps 2.7K@30/50/60/100/120fps 1080p@30/50/60/100/120fps With DJI FPV Goggles V2: 4K@30/50/60/100/120fps 2.7K@30/50/60/100/120fps 1080p@30/50/60/100/120fps H.265 Video format @ 50Mbps	W: 720p@60 fps R: 540p@90fps, 720p@60fps, and 1080p@30fps The VRX outputs HDMI video up to 720p@60fps	1080p@60fps, 720p@120fps, 720p@60fps Transmitter uses H.265 Video format VRX outputs HDMI video as well
On-board video capture		No	Yes 20GB bulit-in storage in the air microSD (up to 256 GB) in the air	No	Yes microSD (up to 256 GB) on the ground 8GB built-in storage in the air
Cost (USD)	Lower is better	Depends on wifi adapters. Need one for air and one for ground. Claimed to be <$100	$230 (No VRX/goggles)	W: $55 H: $70 VRX: $220 + antenna cost Total: $275 - $290 without antenna	VRX: $220 $240-310 with everything included

Other Sources: