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

[phibin]

so im not totaly stupid then..? lol

the 3.3v ftdi will flash it ok....

simon.

[Coyote]

Yeah I use a 5v input, 3.3v output FDTI programmer

[phibin]

But a 3v3 one may well be your simplest option

that is what i thought....
for all the messing, wouldnt it be best to just have the correct tool for the job... lol

thanks again for all your help mate!


simon.

[ghost2212]

Is anyone using 1.3ghz video gear with the openLRS?

Outside the UK of course  :D

[ghost2212]

Is anyone using 1.3ghz video gear with the openLRS?

Outside the UK of course  :D

I use 5.8ghz, what's your theoretical question ghost?

The 1.3ghz gear seems to kill the range of the openLRS. Using the spectrum analyzer I measured a massive peak at around 428mhz spreading to about ~431mhz. With the 1.3ghz I had a range of about 100m before glitching but switch to 5.8ghz and it was instantly a lot better.

I just wondered whether anyone else had managed to use the two together.

[ghost2212]

1.3 will kill the range on all UHF radios, unless you buy a filter...... 1.3 is a harmonic of 433 ;)

its a third Sub Harmonic and people don't seem to have issues with Dragonlink and other LRS

[Coyote]

I argue a filter wont help, the filter blocks higher or lower frequencies for sure, but a harmonic is not a higher or lower frequency its a point where cycles intersect each other. I found that with linear antennas the UHF problem was reduced greatly, but with Circular vtx antennas it is the UHF kiss of death.

[Coyote]

A filter does nothing for harmonics John, fact.

Your talking about higher or lower frequencies being emitted from the vtx, which is not harmonics, which is exactly what I wrote. I was referring to harmonics not being effected which was what ghost was referring to

[ghost2212]

A filter does nothing for harmonics John, fact.

Your talking about higher or lower frequencies being emitted from the vtx, which is not harmonics, which is exactly what I wrote. I was referring to harmonics not being effected which was what ghost was referring to

I'm using linear antenna's, An inverted vee at 1280mhz. I have also purchased a high pass filter which seems to make no difference whatsoever. I need to find a way to check that its actually working(it should have a loss of greater than 40db at 428mhz)

[Coyote]

Please read up on your literature John. Google harmonics

433mhz x 2 = 866mhz
433mhz x 3 = 1.299ghz

Its the cycle of the 433mhz hitting the 1.3 band by the 3rd cycle. That`s called harmonics. As the vtx no matter how many filters you fit to it is still a 1.3ghz transmitter the harmoincs still hit each other.

Please tell me what type of filter you use to stop a 1.3ghz transmitter transmitting on 1.3ghz ?

A high pass filter helps because say the 1.3 vtx was still emitting power on as low as 866mhz then it will be walking all over the UHF reception trying to be received, so a filter help, but it wont stop it at 1.3

Even a bandpass filter ( which I tried ) on the UHF rx can not stop it

[Coyote]

You could band pass the UHF rx, high pass the vtx and use a very high channel. That may help a lot.

[Coyote]

You could band pass the UHF rx, high pass the vtx and use a very high channel. That may help a lot.

Bandpass = filter
Highpass = filter

Hang on that's a complete turn around from 5min ago, glad you googled and finally agree

Lol no its isnt` and no I don`t agree with you.

Its not a turn around, I stated moving the vtx away from the harmonics IE by moving up channels will help, that`s because it gets it away from the harmonics, then with the channel high and out the harmonics way filter out the lower emitted frequencies IE closer to the harmonics.

You didnt mention moving channels to get out the way of harmonics at all, you said just filter, which still leaves you in the harmonics and fixes sweet FA lol 

Like I said though, been there and done it. Bandpassed, high passed, Range tests came back fantastic, real flights proved even by doing all that UHF failsafed like crazy within less than 1km.

[Coyote]

That`s by far the best fix, we agreed on something !!! :)

[ghost2212]

There's an even better fix, run olrs at 459 and use legal video frequencies mutter mutter

I do intend to try 459mhz and see if its less affected by the 1280mhz transmitter.

So your using 25mw 5.8ghz are you? :P

[ghost2212]

I'm on 459 and those fancy new 400mw 5.8vtx's  ;) no need for 1.2ghz as I can get to the limit of my planes battery range on 5.8. Although 1.2 is good for cloud busting :P

5.8ghz is fine for most stuff but the final plan for me is to be able to fly with 3 other people with 2 of them on 5.8ghz so running 3 on 5.8ghz could prove problematic. That and I have 2 1.3ghz vtx's so would like to use them if possible. It has better penetration for going through trees as well :)