1.2gHz Video : 433mHz Control

[volto]

Maybe you guys just need one of these on the vtx http://www.foxtechfpv.com/9001300mhz...ter-p-325.html

[SENTRY]

I ordered one from Digikey - but if the 1.2 LM has a grounding issue I'd try this first - so I'll take a look at that option tonight and see what my ground tests look like.

[stupsi99]

@volto: I actually have this filter on my vtx already!

@sentry: I'm not alone!
I just soldered the following together:
ground wire which leads to Vtx, split soldered to top of housing, -> no change

ground wire from uhf rx (on one of the channels) soldered to top of housing (the other one removed), -> no change

Also when I simply get really close (less than an inch) to the housing with my hand or finger, it leaves failsafe mode again. I am starting to wonder whether we somehow weaken the Vtx radio just about enough with the hand or finger (absorbing it?) to make the uhf work again?

The only way to find that out is drive away further, where the failsafe has set in for quite a long time (which means that weakening the Vtx signal a little bit, shouldnt make the uhf have enough range again or whatever I gather out of my non existing RF-Skills ... ).

Also switching from low to high on the UHF TX doesn't greatly improve the range, it was just about a 100 meter more.

Sentry, I'll read through the thread, thank you.

- Phil

[stupsi99]

I solved the issue for me:

After soldering a wire to the housing and putting either the uhf ground or the battery ground on it, no change in range.

I've then decided to play around with ferrite rings and twisting my wires (for testing I only attached the esc and one servo).
Here's the thing:
Looping the Vtx cable through a ferrite ring two or three times helped increasing the range a lot! When taking the ring off, the uhf went straight into failsafe, putting it on, leaves failsafe mode. I also found out that the placement of the ring has got to do with the range. The closer the ring to the Vtx the better the uhf range got (I tested it in town with lots of houses in between on Low mode). With the ring close to the Vtx, the range was about as much as that time, when I did the test WITHOUT the Vtx turned on!

So that looks like we're gonna have to fly around with a big ferrite-blob on the tail haha

Hope everyone's happy now. Enjoy the flight, I'll sure do now.

-Phil

[FabioMussarlz]

what about wrapping the wires with aluminum foil ?? its a lighter solution than ferrite. But I donīt know if the results will be that good

[SENTRY]

The toroid near the vTx is also the fix recommended by Crist Rigotti. I will be doing that instead of the digikey filter 1st. I think that's the ticket.

[saucisse]

J'son, let me know when you get the filter and the results. I've been playing with 1.2GHz on my quadcopters for some times now and really like it with cp combo from TrueRC. The only down side I see for multirotors is the size of those cp antennas...otherwise range is not really an issue as I fly within 1-2 km from me with my quads.

Had failsafe problem on a small flying wing before but partly solve the problem by spacing the vtx from the UHF rx.

[stupsi99]

@saucisse:

I have one of the filters on from the beginning, I can't tell how it would be without one, but having the filter definitely didn't help.

Or is there a special "lowpass" filter for lower frequencies?

-Phil

[SENTRY]

^^ Which filter did you have?

[Danub]

The toroid near the vTx is also the fix recommended by Crist Rigotti. I will be doing that instead of the digikey filter 1st. I think that's the ticket.

When you test this will you torrid all of the wires going to the VTX? only the power wires or only the video wire?

Stupsi99 -could you plz post a picture of how you placed the ferrite plz.