Flying in a town vs flying in the countryside.

[Girth67]

I normally fly in the countryside on 2.4ghz WIFI, however today I flew in a huge park (hardly anyone about) in a town centre the difference in the spark was incredible....not in a good way.

Firstly my Spark experience to date in the countryside has been a pleasure. Smooth flight, control and video.
So today I followed my normal routine of selecting a 2.4ghz channel with smallest green bar.....to my amazement almost all the channels were red so I considered packing up without flying.
However I thought I'd give it a go.
Once flying the video lag and image quality was horrendous and the normally instant taking of photos was just as bad. Due to The lag control and the flight experience was terrible. So I landed and changed to 5.8ghz which again only had two usable channels.
This time video was much sharper but range was terrible giving warnings at 70m.
The AC seemed to wander and yawl with no input. But control was better due to the reduction of lag.

I'm not complaining as I stated I mainly fly in the countryside and it's the polar opposite of today's events , I just thought the experience should be passed on.

 

[Texas Gonzo]

If you're selecting a channel with the SMALLEST GREEN bar, there is a huge part of your problem with poor range! You want to use a channel with the BIGGEST GREEN bar, not the smallest. With wifi and cellular signals, etc, the smaller (-) value represents a stronger signal strength.

IE: -100 is weak, while -60 is booming. So, a channel showing -60 with a green bar would be more desirable than a channel with -90 or -80 with a green bar. If you see a red channel with say, -60, that's a highly trashy choice, red -100 would be less trashy, but still trashy nonetheless.

It is a bit confusing, and took me a bit to wrap my head around years ago, but, that's the poop on signal strength.

 

[Girth67]

Yes its confusing. I asked this question on the forum a few weeks ago and got the opposite answer. ie the smallest bar is best.
Does the bar not represent channel traffic or interference the bigger the bar the more interference or traffic?

 

[Zoran]

The bar represents channel interference, the higher the green bar means the more interference on that channel... you want to use a channel with the least interference which means the smallest green bar possible is the best one to fly on

 

[Texas Gonzo]

The bar represents channel interference, the higher the green bar means the more interference on that channel... you want to use a channel with the least interference which means the smallest green bar possible is the best one to fly on

WRONG. RED indicates a channel with interference. GREEN should be only indicated on the channel you're currently occupying, or one that is clear of interference.

Try entering *#*#4636#*#* on your android phone and looking into the first section, Device Information>Signal Strength and see how the numbers jive with your signal strength indicator.

Why would they use two different colors to represent the same thing? They don't. The LOWER the negative value, the STRONGER the signal, not the other way around. -100 is weak, -60 is strong. RED is bad, GREEN is good. Atleast thats my experience flying out past a mile on a -60 GREEN channel, and barely makig 200 meters on one thats at say -100 and RED.

I've been home-brewing antennas for over 30 years, along with working along side engineers that design broadcast consoles and commercial antennas....I can't be that far off. Then again, we are talking Chinese software designed to brick the very hardware its supposed to enhance, so who really knows.

Try hitting google or duckduckgo with the terms RSSI, ASU and DBI.

 

[Zoran]

Check out this YouTube video for explanation...make up your own mind:

 

[Zoran]

WRONG. RED indicates a channel with interference. GREEN should be only indicated on the channel you're currently occupying, or one that is clear of interference.

Try entering *#*#4636#*#* on your android phone and looking into the first section, Device Information>Signal Strength and see how the numbers jive with your signal strength indicator.

Why would they use two different colors to represent the same thing? They don't. The LOWER the negative value, the STRONGER the signal, not the other way around. -100 is weak, -60 is strong. RED is bad, GREEN is good. Atleast thats my experience flying out past a mile on a -60 GREEN channel, and barely makig 200 meters on one thats at say -100 and RED.

I've been home-brewing antennas for over 30 years, along with working along side engineers that design broadcast consoles and commercial antennas....I can't be that far off. Then again, we are talking Chinese software designed to brick the very hardware its supposed to enhance, so who really knows.

Try hitting google or duckduckgo with the terms RSSI, ASU and DBI.

Keep in mind it's showing channel interference, NOT signal strength... The less interference the better...

 

[Texas Gonzo]

Also, why not just leave channel selection on auto and let the app decide to start with?
The devs have these things called "algorithms" designed to instantaneously look at all the available channels and decipher which ones are clean vs trashy, then chooses the best option for that moment, in that location. That's how I fly 99% of the time with my Spark and P3S, and typically have no trouble reaching beyond the maximum range listed in the specs for both birds. Range wise, 2.4ghz is better than 5.8 due to wavelength, however the reverse is true for quality at shorter distances.

I use an OTG cable while in airplane mode for the Spark, which makes a world of difference with fpv quality in my experiences thus far (100+ flights and well over 50 total flight miles since Sept 23rd of this year between the two uav's). A hardwired connection always trumps wireless for stability and less interference, especially in over-crowded areas... not to mention increased battery life on the [fpv] device being used since you can turn wifi off all together. Wifi is a bigger battery hog than even cellular data on all of my phones and tablets.

As always, your mileage may vary greatly depending on a number of variables....

 

[Zoran]

What ever works for you is the best option, but all I know is that I've been sticking to the rule of the smaller the green bar the better, and I've had no issues at all with the signal...just yesterday I flew my Spark 750 MTRS away from the RC @ 80 MTRS high on 5.8ghz with no OTG cable in a heavily wooded (tall trees) area, so the smallest green bar seems to work for me, so I'm sticking to it.

 

[Girth67]

This has been causing me some confusion for a while.
I appreciate any ideas or discussion on this topic so thanks to Texas Gonzo and Zoran for your posts.

What I will say is on looking at the video as the bar rises going from -100 towards - 60 on the scale as it hits -90 it changes red this gives me the impression (as the guy in the video states) that the bar indicates traffic or interference on that channel. I can't remember if I've ever seen a green bar at a value of say -80 or not.

As a result I'll carry out my own tests and see which works best and which size of green bar gives the best signal obviously on both 2.4 and 5.8ghz as they have different ranges....work, weather and kids permitting.