thUndeadMod v3.4 - openLRS S**T just got real :)

[zitron]

So my noise floor analysis is -73dB and with the Tx on its -7.5dB

Ok so now I have these figures what can I extrapolate from them?

Huh? How did you get -73? At 459MHz with nothing on, you graph shows peaks of ~80. 80/2-130 = 90dB, which is exactly the same as mine. The RF22 board needs a signal that is something like 3dB above the noise floor to work, so the lower the noise floor the longer range your will have.

There's not much you can extrapolate from this, apart from the fact that your noise floor looks normal, I think. You can try different antennas and see what RSSI peaks you get. But you should really do that at lower power or longer range, because if the signal is too strong the (raw value >200) the response will not be linear. You can find a graph of RSSI value vs dB in the RF22 data sheet.

[papa_lazerous]

I don't understand how 80 divided by 2 minus 130 =90 ???!  Wouldn't it be -90?

I did 114/2-130=-73

[Coyote]

Yeah i get -73db also from your graph, which is still high to me, when PK and I tested noise floor with an rcexplorer ( spectrum analyser ), even in close proximity with a gopro switched on our peak values ( which was the Gopro ) was -120db. Which does not match any of my scans or Papa`s 

[zitron]

I don't understand how 80 divided by 2 minus 130 =90 ???!  Wouldn't it be -90?

I did 114/2-130=-73

Yes sorry -90.

You are reading 114 at 432MHz, what you are interested in is the graph at 459MHz which is 80!

[papa_lazerous]

Ok Zitron I understand now :)

[zitron]

Yeah i get -73db also from your graph, which is still high to me, when PK and I tested noise floor with an rcexplorer ( spectrum analyser ), even in close proximity with a gopro switched on our peak values ( which was the Gopro ) was -120db. Which does not match any of my scans or Papa`s

Yeah I don't think -120db is realistic. If the noise floor was really that low, you would theoretically be able to get >50km range at 100mW!!

Try it with this range calculator: http://abicom.co.uk/documents/rf-calculator-3.0.xls

[raptor_flyer]

thUndead,

Using your code on 459, we are just about to do some serious (airborne) range testing in the next couple of days.

One enhancement request :-

Can you possibly add back in the line (from the original flytron code) in the TX code for future releases :-

if ((transmitted==0) && (channel_count>3) && (channel_count<13))

just before :-

Green_LED_ON;

in the main loop since this ensures it stops transmitting if there's no valid PPM frames coming in.


Also found one very very minor bug :-

#if (TX_BOARD_TYPE == 3)
 
-- deleted lines

    #define Green_LED_ON  PORTB |= _BV(5);
    #define Green_LED_OFF  PORTB &= ~_BV(5);    // Was originally #define Green_LED_OFF  PORTB |= _BV(5);   E.g turns it ON not OFF
   
-- deleted lines

#endif   

It looks like this came from the original Flytron code

Thanks Steve (aka Ghost2212's Dad)

[BlueFlyer]

just installed the v2 hardware today, using a turnigy 9x for my tx. got 1km range before failsafe kicked in. This was by me leaving the TX switched on and left on a bench in my garden. I'd configured failsafe to move a servo. took the rx and servo for a drive and managed to get to 1km with houses, trees, walls and a big hill between the TX and the RX, while it was in my car.

Cant wait to flight test the range of this baby.. I also have the booster which I'll obivously only ever use in emergencies to regain control when out of range ;)

[papa_lazerous]

You got 1km without a booster? Exactly what frequency where you on and what version firmware? I'd be more than impressed of you got 1km on 459mhz but I doubt this is the case

[thundead]

hey bud, cheers for the bug report :) All noted and will be in the next fw update.

Mihai.

thUndead,

Using your code on 459, we are just about to do some serious (airborne) range testing in the next couple of days.

One enhancement request :-

Can you possibly add back in the line (from the original flytron code) in the TX code for future releases :-

if ((transmitted==0) && (channel_count>3) && (channel_count<13))

just before :-

Green_LED_ON;

in the main loop since this ensures it stops transmitting if there's no valid PPM frames coming in.


Also found one very very minor bug :-

#if (TX_BOARD_TYPE == 3)
 
-- deleted lines

    #define Green_LED_ON  PORTB |= _BV(5);
    #define Green_LED_OFF  PORTB &= ~_BV(5);    // Was originally #define Green_LED_OFF  PORTB |= _BV(5);   E.g turns it ON not OFF
   
-- deleted lines

#endif   

It looks like this came from the original Flytron code

Thanks Steve (aka Ghost2212's Dad)

[Coyote]

Well I went out for more flying today, I flew the wing LOS to trim it up, flew quite nice, on OpenLRS

Next up was the Skywalker, I flew a few circuits, put the goggles on, and then it began...........

Only 200 m out, RSSI dropping from 2.8 to 0.04, up down up down, as quick as you could say it, could not get control back, one smashed Skywalker, at only 200m !

[thundead]

shit...  that was on 459 not on 435 right ?

[Coyote]

No that was on 435, my japan-DVR recorded it, but file was corrupt, Ive just found a way to save the file, and when I did, something very interesting is there, just converting file to show you.

When I did my first launch, that went badly, I thought nothing of it and launched again, but seeing the footage as soon as I let go of it it looses link instantly, hens the crashed launch

[thundead]

hmm really strange. would be grat if u can make like a log.

[Coyote]

fault1.MP4

As you can see, which I couldnt at the time, right next to me the RSSI in the top right shows full to 0 full to 0