FPV Receiver Not Outputting AV Signal

vtx
fpv

#1

Hi, I purchased the following:


I have both of them on the correct frequency and when I plug the receiver into a tv, I get no signal.
The VTX and camera are warm so I assume they are transmitting fine, but the receiver isn’t doing anything other than the red light turning on.

Any suggestions? Thanks.


#2

Hi
Some really basic first checks…

What receiver antenna are you using ? (this receiver is not supplied with one by HK so you need to add your own)
Check the polarity of the RX antenna connections ( SMA or RPSMA) It is possible to fit both halves which have inner sockets and there is then no connection, one side should have a pin.
Is the TV set to the correct AV input source for ‘composite’ video ?
Is yellow plug in video, with red & black plugs in the two audio channels ?
Do you have sound but no video or nothing at all ?
What power source are you using for the reciver ?

Maybe this will put you in the right direction
Cheers
Steve :slight_smile:


#3

Hi @stevietee10.

I’m using these antennas: https://hobbyking.com/en_us/aomway-5-8ghz-4-leaf-clover-antenna-set-for-tx-rx-sma-rhcp.html And on the receiver I am using an adapter(http://www.ebay.com.au/itm/321942627521?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT). I didn’t bother plugging the sound cables in as no sound is being transmitted, the yellow video plug was definitely in the yellow input on the tv. It was the right source on the tv I checked it with a dvd player. I also tested the receiver on a different tv with no luck. I’m using a 2S battery to power the receiver.

Is the problem perhaps that the transmitter uses “Wideband FM Modulate” and the receiver uses standard FM? If it was receiving no signal would static just be displayed on the screen? Could it just be a faulty receiver?

Thanks Stevie.


#4

Hi @Verpz

Accepting the spec says min. voltage is 7v and suits a 2S pack, I’ve found that these can be unreliable at bottom end voltage so I suggest you try a 3S pack or at least 8.5v from a PSU
I can’t comment on the WFM/FM specs as don’t have a lot of RF experience hopefully somebody else on the forum can advise you on this
Yes, if the Rx was doing anything I would expect to see static on the TV so if a high supply voltage does not work it is looking very much that you have a ‘dud’ receiver.
Good luck with HobbyKing :cold_sweat:

Cheers
Steve :slight_smile:

PS. Do a continuity check on the AV cable, a long shot but worth a minute :grin:


#5

Yeah no luck, trying to get a refund/replacement from HK.

Thanks for your help :slight_smile:


#6

Good news!

The AV cable was just wired wrong. FPV is working. Now I’m just waiting on the EASYCAP and then I’ll post a guide on how to get FPV on your phone.


#7

I had the same symptoms and if it can help somebody, here is what the troubles were:

  • Too low voltage for the FT48X tx even though it looks like running properly. I had to pick the power directly from the PDB rather than from one of the motors (well the specifications says 6.5V to 25V, I should have known better).
  • Strangely enough the frequency table does not seem to fit. After testing I set the FT48X to band A channel 1 (5865 Mhz so the user guide says) and the FatShark to the race band (band E I suppose) and channel 7 (5880 Mhz if I read right). If somebody could enlighten me :slight_smile: