HELP! 2.4GHz FPV System refuses to get signal!

Hello Everyone, 

My FPV set up is a 500mW 2.4Ghz system, and I cant get the VTx to establish a connection to my Vrx. I always get the "No Signal" + static on my Hobbyking DIY FPV V2's. Before I start the description, below is a list of the equipment I'm using. Pictures of my wiring, and a drawn schematic of the wiring, are available at this link --

Flight Controller: HKPilot 32 (Beautiful Hobbyking Pixhawk Clone) 

Video TransmitterTBS Unify 2G4 500mW

Video Receiver: Lawmate RX-2460

CameraQuanum Super Mini 520TVL FPV Camera

OSD: Micro OSD (Smaller MinimOSD derivative designed to perfectly fit Pixhawk & APM)

I'm pretty confident my wiring is fine, because everything seems to be getting power with all the correct LED lights lighting up. I know the camera is on because it get a bit warm too. The problem begins when I switch both my FPV systems on. I've tried all channels 1 through to 8 by adjusting the DIP switches on the RX & TX accordingly, but I still always get "No Signal". 

I've even tried connecting the vtx straight to the camera and BEC, without the OSD in the middle, and I still didn't manage to get a signal. Hence ruling out the possibility of the OSD being the problem. 

I did notice however that when I got the Antennas of the VTX and VRX very close, the constantly appearing and disappearing horizontal black lines in the screen static would disappear. They would then slowly re-appear as I brought the antennas further away from each other again. 

I am currently set on the Channel 1, 2410 Ghz band on my Vtx and Vrx. 

I've spent a lot of time, effort, and money on this, so any help on getting this work would be massively appreciated :):D

Thank You!

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    • hey Clifton, you there man? 

    • Yeah.  Snowed in.  What's up?

    • soz about the long replies in the thread. If you don't mind, could you have a read through and let me know what you think/if you have any ideas? Cheers!

    • I think I may have a lead on the problem. I think it is to do with the weird AV pin out Lawmate accepts/recieves vs. the AV arrangement of the Quanum DIY FPV V2 goggles. Note that these two accept those headphone jack style 2.5mm connectors for AV connection, instead of the usual large round yellow white and green RCA/Component connectors (of which I have adaptors for for the headphone style connectors). 

      Anyway, in this manual ( it explains the AV pins on the lawmate receivers on page 8 out of 22. 

      If differing pins is the issue, then the only way possible to try and figure out if this is the issue is to try and combine different permutations and combinations of those RCA/Component input and output wires between the RX and the screen. I did this but I still cant get a video signal on my Quanum FPV screen (which we've established already works). Even tried it on another tv I had with AV IN. 

      If there is anyone out there who has used Quanum FPV DIY goggles with a Lawmate Receiver, if they could verify that they work together with just the headphone style connector straight in, then I can rule in that it is my TX or RX that is definitely broken. Problem is finding this someone. 

      Do you have any ideas?
    • The cable connecting the receiver to the screen, is that one that came with the receiver or from something else?

      You will need to use one with the correct pin assignments to match the lawmate receiver and they look pretty unique to lawmate. If you have a multimeter and can solder you can adapt what you have to work though. You would need to cut and strip the cable coming from the headphone jack plug (should have red, white, yellow and common shield). Then use the meter to see which pins on the jack relate to which cables, use the pin assignment from the eztracker manual you linked to to work out which two wires match the lawmate pin arrangement for ground and video and attach a yellow RCA to those two wires.

    • lol, also, Lawmate is apprently really widely used in FPV. since thats the case, should they have some sort of standard pinout, giving reason as to why so many people use them without seemingly so much hassle. 

    • Probably find that they are being connected with lawmate specific cables, as that eztracker manual shows lawmate have there own pin layout for the mini jack that no one else uses.

    • yeap, had same problem some time ago, immersion rc rx pin layout of the output jack is  not standard as tv's or cameras ones

    • No Cable came with the receiver. The one from the screen is pre-wired to it, and coupled to an XT60 input for power. It seems to be quite a huge hassle for something so small. The weirdest part is, in the manual that Hobby King's DIY FPV V2 Goggles came with (ie my screen), it looked like it had a standard lawmate attached to it on its side as if it was supposed to work stock. 

      Also, when using a multimeter, how would you distinguish between the audio and video channels? (im guessing out of 3 rca cables, one is for ground, one for audio and one for video?). Not to mention the individual fat rca cables have ground and signal as part of its connector. hence in the youtube video i posted and linked i was able to receive video by only connecting the video rca connector.  

    • The RCA is red for right audio, white for left audio and yellow for video.

      The inner pin of the RCA connector is the signal and the outer ring is the ground.

      So, where did you get the mini jack to phono lead from? If it's not wired up as the lawmate needs it then you won't get any video signal to the screen.

      If you have a multimeter,do a continuity check between the mini jack rings and tip and see what each ring is connected to of the RCA plug's.

      So tip goes to ??

      next ring goes to??

      next ring goes to??

      base ring goes to?? 

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