25 mW: the number on the VTX box that Sweden actually enforces
Video transmitters are sold by the watt. Swedish radio law allows a fortieth of one on the band most of them use, and the antenna counts too.
What this is written from: Written from PTSFS 2025:1, the Swedish Post and Telecom Authority's regulation on licence-exempt radio transmitters (in force since 17 March 2025), from DJI's published O4 specifications and from CADDX's announcement of the Walksnail GT2, read on 29 September 2026. Not legal advice.
The watt on the box
Analog video transmitters are sold on their top power: 800 mW, 1 W, and this spring Walksnail announced the Avatar GT2 at up to 2 W. It is the headline number because range sells.
Using a transmitter without a licence in Sweden is governed by PTSFS 2025:1, and on the 5.8 GHz band that FPV video lives on, it allows 25 mW. Not 25 mW of output: 25 mW e.i.r.p., which is what leaves the antenna, gain included. A transmitter set to 25 mW with a high-gain antenna on it is, strictly, over the limit.
The limits that matter for a drone
PTSFS 2025:1, licence-exempt use. e.i.r.p. includes antenna gain.
| 5.725 to 5.875 GHz (analog and most digital video) | 25 mW e.i.r.p. |
|---|---|
| 5.15 to 5.25 GHz | 200 mW e.i.r.p., and drones only between 5 170 and 5 250 MHz |
| 5.945 to 6.425 GHz | Not allowed from drones |
| 2.4 GHz, data transmission | 100 mW e.i.r.p. |
| 863 to 868.6 MHz (900 MHz control links) | 25 mW e.r.p., with duty-cycle or listen-before-talk conditions |
What this means for the thing you are about to buy
For an analog transmitter the question is not how high it goes but whether it has a 25 mW step, and whether that step is honest. Several in the catalogue list one explicitly; the product pages say which. A transmitter whose lowest setting is 200 mW is a transmitter you cannot legally switch on here without a licence. An amateur radio licence allows more on part of the band; whether that extends to a drone in Sweden is a question for PTS, and this post does not answer it.
DJI handles it with a region mode. Its published specifications for the O4 air units give under 14 dBm, about 25 mW, on 5.8 GHz in CE mode, and under 23 dBm, 200 mW, on 5.1 GHz, which are the Swedish figures almost to the decibel. The cost is range: DJI rates the O4 at 6 km in CE mode against 10 km in FCC mode, and the O4 Pro at 8 km against 15 km. Those are the numbers to compare, not the FCC ones in the review you watched.
Where this goes next
- Every video transmitter, with its power settings Which ones have a 25 mW step, and which system each speaks.
- Video systems, explained Why the transmitter and the goggles have to agree first.
What Buildlas checks for you here
Every rule is published, with what it reads and what it does when a specification is missing.