I flown today around a simple, empty field with literally no obstacles on the way and was really disappointed with range that TX805 gave me. Never flown with FPV camera on board so please correct if my expectations were too big!

VTX Eachinge TX805 25mW - havent tested higher mW yet
Receiver with LCD Eachine Moneagle
Camera Runcam Phoenix 2

I suppose pit mode is off since I dont expect I'd get even this distance with pit mode on.
Connections between VTX/receiver and antennas are correct.
VTX has pagoda installed, receiver has pagoda + patch (true diversity capability). VTX antenna is heading the sky

After reaching 100 meters distance I started to loose signal. After 200m I lost it compately on relatively low height. Plain field. No trees, building on the way as you can see on the short video. Once I turn around video comes back but it starts to worse I fly over myself/receiver.



Please, advise if I am expecting too much or there is something wrong with my setup.

Thanks, m

The TX805 is a very budget VTX at $20 and the power output is not very accurate. For a cheap VTX's at 25 mW the range you are getting is probably as good as it gets.

Some may argue about antenna placement and better antennas and being able to get ridiculous range out of the cheap VTX they have but unless you have a baseline how can one be sure.

What do the LED's say on the vtx? Are you sure you are at the correct power levels?

Just bump it up to full power and see how far you can get.

https://oscarliang.com/eachine-tx805-vtx/
its truly an inexpensive vtx but it seems not that bad. i used few eachine vtxs and they worked all very well, didnt gave interferences to other channels...
one time i miss configurated the vtx, flew with two buddies one was on 25mw and one did use a higher power probably 400mw. i was on 10mw accidently and was able to fly okish in short range, impressed me :-) the eachine vtx03 does output more than it should, somehow a downside to fly with buddies and eomehow not acceptable for racing but everything else is very good.

i would care about airflow as oscar mentioned the heatsink, how did you mount it?
normaly the antenna placement is easy on a plane as there is space and less interfering materials, but you could show us your antenna placement

do you maybe power it on 5v? the voltage range is 7-24v

If pitmode is on, you wont make 10m.

If antenna is not fully connnected, you will barely make 100m.

Not all vtx 25mw is "25". Some output bit more. Some much less.

Make sure to try at least 3 frequencies. ie B1, B4, B8

Some vtx put much more power at low frequency. Some places have lots of 5.8Ghz Wifi.. >5860Mhz helps a lot.

Thank you all for your responses and interest.

kafie1980 
I am absolutely fine if this cheap VTX will give me 200m top. But I have seen other ppl using same VTX and doing KMs with not much better hardware than I have - that is why i want to find out what is wrong. LEDs (all light up) show "800mW" now. I tried on 25mW yday. Will bump full power as you suggest and try again.

hugnosed_bat
Airflow is delivered, I will consider heatsink - but that is long term solution to prevent issues with long flight. Mine issues start at the same minute of powering up so I dont think we should consider overtemp ath this moment. I am powering it with 9v (via FB Matek H743-wing).
This is my antenna placement (top of the plane):

and air access (opposite side of the wing)


romangpro
I will test other frequencies - havent done that either next to changing the power. Thanks for suggestion.

Also ensure you manually set the same band/channel in both your goggles and vtx.

(10-Sep-2021, 03:11 PM)kafie1980 Wrote: Also ensure you manually set the same band/channel in both your goggles and vtx.

Even if I use autosearch option?

that looks all good. 9v is perfect...
autosearch is a source of issue, hide autosearch :-) maybe its that.

Never use autosearch to tune a VRX to a VTX. Only use manual tuning on goggles to the exact same band / channel / frequency as the VTX is broadcasting on FTW

Thank you all for support.
I will test all your advices and let your know if that worked.

Hey - sorry for long time with no answer.

So I used all your suggestions - used max power at VTX (800 mW per eachine), checked all antennas connectors, used specific (5680 Hz, havent tested different tho) freq and matched it manualy with the screen I am using.

As the vid below shows i reached 420m and started to loose signal heavily. Then I turned back and kept having bad signal - even if I was heading straight back home (240m away and I still had a bad sight 01:19).
https://youtu.be/T1Gf4yUhkO4?t=59

I dont want to bother you all and solve that as long as it is perfectly normal and I need to get used to that. Maybe videos (https://youtu.be/HmiUqzg2HDY?t=104) of the very same VTX showing few KMs distance used much better antennas and much better video receivers that I am using (but personaly i doubt that so I try to dig what is wrong) - I dont know...

Do you have access to another vtx or quad or plane that you can benchmark the range you are seeing?

It can be your goggles or your vtx. I will not want you to spend more money buying the same vtx again but I am worried about asking you to buy another one as it may be your goggles module.

Hi! I've seen reviews on the Eachine Moneagle and poor sensitivity ratings for this monitor.

I agree with others, it is better to test VTX with other tested goggles-antenna set.

Thanks guys for your effort. Seems like not that easy case to be solved out. I dont have anyone handy to test it, I'm rather an outsider among my friends with such a hobby :-). I do have other VTX but also rather cheap with less power, therefore frankly speaking i do not expect much better ranges. Thanks tho! I appreciate your help!

there are some inexpensive "eachine otg receivers" able to provide video to an android or ios device.
i watched a 5k flight of a buddy, the video receiver is pretty decent for the low price - maybe it could be good 20bucks ti check how your actual receiver works.