Does anybody know where I could pick up the the antenna signal on the VTX of the Tinyhawk Series (1-3) instead of the regular antenna pad?

Already tried to find something with the mulitmeter connection test but without any luck. (Maybe somebody even has a diagram of the board layout?)

Thanks in advance
Wasp

I believe that is the only "pad" or signal output on that vtx... if ur looking for more range, there are plenty of VTXs that will fit on that compartment once the stock one has been removed.

Since I've tried to keep it short for readability, I guess you got me wrong. This is a repair attempt.
Yes, I would like to have more range, more than 2 meters. ;-)

So I'm not necessarily looking for another pad though I would prefer that of course. I'm looking for any contact to get a solder connection since the former owner ripped the pad off I guess -- however it is short to or literally ground itself. (Not sure how the tracing on this board is arranged.)

yeah, I get it...and honestly the eachine nano vtx is a good alternative if u cant locate a pad/pin for the antenna...
also, it also depends on what vtx u have. I just pulled out some i have removed,.. they do not have the same layout. I know Emax went to a 200mw vtx, but there is no markings as to what one is what. I looked REAL close to both, I cant find any "trace" on either VTX.... sorry.
Emax's response to questions like this is not the greatest. I asked about the controller POTs in their RTF kits..(one i had had a choppy throttle- you could see it in betaflight).. I wanted to know if a PS4 or Xbox controller POT was the same (since they are so cheap)... I ended up just swapping it, it works, but the "sweep" is shorter.

Thanks for your effort.

Yeah, I'm a bit on the trip of: that must work somehow! Plus it's a good lesson for me I guess though maybe the wrong difficulty to start with (size wise).

   

I wonder:

1. what is the silver part next to the (broken) pad. As far as I can tell it carries ground though I'm not 100% sure since my mulitmeter probes are pretty bulky .. relatively speaking.
   
2. There is the light "dot" in the pad in-between the green shimmer -- not sure what this is. I wonder if this is the trace below the pad I'm kinda looking for.
   

Anybody any ideas?

I do not have a Tinyhawk AIO board to confirm and probably someone can do some continuity tests to confirm the exact source for the signal pad. You can try and carefully scrape some solder mask around the signal pad to see if you can find a trace.



Blue pads: Ground
Red pad: Signal
Yellow components: Likey candidates for the signal.

If you are going to work on small board then get your self some needle probes for the multimeter like these. They cost like under $5 from AliExpress.

Thanks for the effort and pictures.

(30-Aug-2022, 01:51 AM)kafie1980 Wrote: I do not have a Tinyhawk AIO board to confirm and probably someone can do some continuity tests to confirm the exact source for the signal pad.

That's quite literal my initial reason/request on this thread:

• "Does anybody know where I could pick up the the antenna signal (...)"
  
• "Already tried to find something with the mulitmeter connection test but without any luck."
  • "Maybe somebody even has a diagram of the board layout?"
    

(30-Aug-2022, 01:51 AM)kafie1980 Wrote: You can try and carefully scrape some solder mask around the signal pad to see if you can find a trace.

(30-Aug-2022, 01:51 AM)kafie1980 Wrote: Yellow components: Likey candidates for the signal.

Had similar idea before I posted here, that it should be something in proximity but "without luck".
To be fair, I had to kinda fat-finger this because of my probes but to increase probability I've just tried all components on the front of the PCB a second time. Couldn't find any connectivity.
Ffront side is already a bit wonky but for the same reason testing of backside practically impossible.
(Should mention, that have the board twice but not worth much since ... yeah probes. Should order the ones you mentioned soon, so they at least have a chance to be here by ... January? ^^)

(29-Aug-2022, 09:58 PM)Wasp Wrote: There is the light "dot" in the pad in-between the green shimmer -- not sure what this is. I wonder if this is the trace below the pad I'm kinda looking for.

Realized in real life this is a lot more pronounced. Not sure why it appears different in the picture and more importantly: who is right, my eye or the camera.

Here is another picture through my actual (cheap) magnifier:


So in the meantime I've tried to get rid of the silver stuff around the broken pad treating it as solder without success. So I've tried very gently to scrape it but without noticing any impact. Since kafie1980 also mentioned I shall just try to scrape the masking of: how/with what would I do this at best? Tried pointy pincette and box cutter. Correct tooling? Should I just try harder?

In this regard I also have this silver/solder right of the broken pad (X1 in the marked picture) which seems to have no contact to ground. This could be helpful however don't know what to test this against.

What are your ideas about the already in the former post mentioned "dot" in the middle? (X2 in the marked picture)?

Your photos are not helping resolution wise but do you see any vias next to the ripped off signal pad? I have a Tramp HV and the signal pad on that vtx actually connected to a component on the backside of the PCB through a via (covered by a shield).

I can only provide educated guesses. Perhaps someone else on the forum with a Tinyhawk board can help do so continuity tests to confirm.

Alternatively, did you try asking Emax support? They may be able to provide a cropped pcb layout showing the signal trace path.

(30-Aug-2022, 02:30 PM)kafie1980 Wrote: Alternatively, did you try asking Emax support? They may be able to provide a cropped pcb layout showing the signal trace path.

Let me answer this with a quote from above:

(29-Aug-2022, 06:45 PM)Rob Axel Wrote: Emax's response to questions like this is not the greatest (...) I ended up just swapping it (...).

However, I could give it a shot...

(30-Aug-2022, 02:30 PM)kafie1980 Wrote: Your photos are not helping resolution wise but do you see any vias next to the ripped off signal pad? I have a Tramp HV and the signal pad on that vtx actually connected to a component on the  backside of the PCB through a via (covered by a shield).

I was already suspicious about the dot in the middle. Remember I've said I have the second VTX of this type but due to bulky probes I cannot really test? Well, while swapping the VTXs now *I* ripped the pad of the second one by trying to bend the cheap one-wire antenna out of the way.



I'm pretty confident now, it goes to the other side.   

Does anybody has the same still laying around after an upgrade for example and can figure out the corresponding trace on the backside? 

I’ll look at all the TH VTXs I have. .. some that I have already looked at .. the trace does not pass through the bottom..I’ll post some pics..
do u know if this is a 200mw vtx or the older 25mw?

We Here are a few of what I have.. u can see the difference in one of the three.. I THINK is a 25mw, but I could be wrong.. and like I said “Emax, isn’t the greatest with questions like this..
If u want.. pm me ur address.. I’ll send I one of u don’t find a solution ..
I looked at ur pics again.. there maybe enough to solder to.. just use some good flux, solder and a small tip to heat that pad..

Thank you for your commitment Rob!

(31-Aug-2022, 12:25 AM)Rob Axel Wrote: do u know if this is a 200mw vtx or the older 25mw?

According to EMAX's Website it should be 200 mW.

(31-Aug-2022, 01:07 AM)Rob Axel Wrote: I looked at ur pics again.. there maybe enough to solder to.. just use some good flux, solder and a small tip to heat that pad..

Which one do you mean, since I've two (broken) ones too. The first one, with the coloured picture and the "last" one I ruined myself (picture with red background).

You think with the flux the solder fits into the hole? To be fair I've no idea how physics play out here because I know that for example for water on this almost or maybe really micro level properties work different from what one would expect...
For exmaple I just recently learned that depending on the manufacturing the whole board could be GND. This would/could mean that if I add solder there now I produce a short circuit and assumingly never get it out again nor have the chance to solder the antenna to the other side. (So at least I would like to understand a little better what I'm dealing here with.)

Do you already have experience with this kind of operation?

@Rob (or anybody else): do you have needle probes? Could you check the backside for connectivity to the pad? My first candidates would be of course one of the two components/capacitors directly on the other side:

Yup, u you nailed it.. this is the only pad I get continuity from the antenna tip.. not sure how u will “shield” the antenna wire .. there maybe a ground nearby.. if it fails .. my offer still stands.. I’ve got like 5 th VTXs sitting on my bench..