Does FCC hack affect flight duration

I’ve just installed my Drone-Hacks FCC, alititude limit removal and NFZ hack (Mavic 2 Zoom). Pleased and surprised at how easy and quick it was - 5 mins. Tried a quick flight to confirm all OK but I hit my 25% battery warning very quickly. I assumed there was less juice in the battery than I thought. Obviously transmitting at a higher wattage will reduce flight time but to what extent? I put a fully charged battery in and left the drone to hover at 22 m in a slight breeze.
I recorded the battery % every minute. After 21 mins the battery was at 20% and I ended the test. It loses a consistant 4%/min. (the battery has had 50 recharges over its life). I wish I had conducted this test prior to the hack so I could compare the two results. It has raised questions about how transmitting power is regulated within the drone.
Does the FCC mode significantly affect flight duration? Does the drone transmit at it’s highest output all the time regardless of it’s distance from the controller? Or does it attenuate accordingly? Any thoughts?

Nothing measurable.

If it did, all remote control drone and other toy manufacturers would be quoting two sets of battery life on their spec sheets.

Is what I was typing, I’ve noticed no difference whatsoever.

I have noticed when using drone tweaks FCC I get slighlty less battery life. I can’t prove it but surely boosting the signal strength will use more power? I’m not talking a lot, but a drop of about 15% is what I find.

I think @Nidge might be the best person to ask this question

My theory is it will reduced the flight time but by how much I can’t answer

If the transmission was constant, commonly referred to as 100% duty cycle, the drain on the battery would be very significant. However the transmission is a high rate of on and off keying, or in bursts as packets of data are being sent that need to be acknowledged by your controller.

I suspect the primary cause of your reduced flight times is seasonal. Batteries are less effective at low temperatures and this has a significant impact on your flight times. If you were to repeat your hover test indoors at room temperature you’ll see a significant increase in flight time compared to outdoors.

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in true Homer J style DOH!!!

I can’t believe I never thought of that. it’s only been the last month or two that I’ve been noticing it

You’re point about low temperatures is one I had forgotten about. It was cold when I did my test.
I can see that control commands to the drone are relatively infrequent but with HD video being transmitted all the time, isn’t this equal or close to a 100% duty cycle? If not, any idea what the duty cycle is as a matter of interest or where a good source of info is on the subject might be found. I like to get into the weeds. Thanks.

Does the fcc hack boost the video transmission too? I thought it was just RC/drone signals? After installing DT I still get video feed issues, but not signal strength issues. Not that I’ve tested beyond VLOS of course!

The video transmission is digital and sent in packets. The receiver will confirm that it received the packet before the next one is sent. If the receiver detects a failed packet it will request a resend. This is why digital signals always have higher latency than an equivalent analog signal. The latency on a Mavic video signal is around 130ms. HDzero has a much lower latency figure as it uses less in the way of error correction. The DJI and Caddx digital FPV systems have greater penetration but they use more error correction than HDzero.

What the actual duty cycles of these systems are I couldn’t say. It’s not something a manufacturer would go out of their way to publish for a consumer product.

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