Twice now I think I fried a vista unit? I had the negative battery lead come off two seperate but same flight controller and short it out. In the process I think it killed the vista but not sure. Installed vista onto different quad and it powers up and I get video but it wont cone out of low power mode upon arming and also won't display batt voltage. I have double and triple checked the tx/rx to rx/tx and also correct uart betaflight and telemetry enabled and the 115200 thing. Does this mean vista is toast? Video is fine until you fly away. Is there a refurbish site or anything anyone know about?

If you are connecting your Caddx Vista direct to LiPo voltage then this is usually caused by a over-voltage spike. Reverse polarity can also cause the same. It is recommended to use a low ESR capacitor across the LiPo connection on the FC / ESC (whichever the LiPo is connected to), or power the Vista from a regulated power supply instead of direct from VBAT.

The Vista has protection diodes on the inputs to the serial data lines which act like mini fuses and these can "blow" in the event of the scenarios just mentioned above. You can check if any of the diodes are blown by using a digital multimeter in continuity (beep) mode to test if any of the SBUS / TX / RX connections have a short to ground.

The Vista will only switch from low power to high power mode when it receives an "armed" signal over the MSP serial data connection from the FC, so if that connection isn't working then that is why the Vista will be remaining in low power mode, and also why you aren't getting the LiPo voltage displayed in the DJI FPV Goggles OSD.

You have one of the following 3 options:-

1. Contact Caddx / DJI and send the Vista back for repair.
   
2. If you have the skills and equipment, replace any blown diodes yourself. The part number of the diodes is PESD5V0V1BL.
   
3. Bypass any blown diodes by soldering a jumper wire across each one to short it out (or remove it entirely and bridge the contacts with solder or a short piece of wire). EDIT: Remove the diodes completely --> you do not actually need to bypass them with a piece of wire. Beware that if you do this and you end up with another over-voltage spike or reverse polarity issue again it will then kill the MCU in the Vista because you have then effectively removed the diode protection on those data lines.
   

The 3 diodes in question are shown in the photo below below. You need to remove the heatsink from the Vista to get to these. It's the TX and/or RX line diodes which will be affecting the MSP data connection.

Thank for the info. The two I killed are useless now so will try jumping the diodes. Also thanks for the picture cause that would have been my next ? I use a capacitor on the battery lead right at the xt60 connector on all builds as I run 6s.

I can only assume I'm having this same issue. I bought my Vista used from a good friend of mine (confirmed working before sending). I've tried EVERY step I can find to try to get OSD in my goggles, including a new FC. Did all the proper steps (rx-tx, tx-rx, enabled correct uart msp, turned osd on in BF and on goggles). Goggles continue to stay on Low Power Mode and will not receive any information from FC to Vista. I have a co-worker that used to repair these types of boards and said it was no issue at all for him to remove those diodes. Does anyone know the model of those so I can replace them, or is it better to just solder the connection? I run 6s with a large capacitor, and power the vista via the TMotor F7 HD.

(15-Apr-2021, 03:24 PM)BunkrdU Wrote: Does anyone know the model of those so I can replace them, or is it better to just solder the connection?

If I had a choice and could find replacement diodes, I would replace them rather than just bypass them.

Are you able to get any close-up photos of the diodes and/or get any identifying numbers and letters from them? Unfortunately I don't have a better photo than the one I posted.

(15-Apr-2021, 04:32 PM)SnowLeopardFPV Wrote: If I had a choice and could find replacement diodes, I would replace them rather than just bypass them.

Are you able to get any close-up photos of the diodes and/or get any identifying numbers and letters from them? Unfortunately I don't have a better photo than the one I posted.

The reason I was asking is based on the cyclonefpv video about removing the diodes, it seems like all he did was remove them. Didn't resolder or bridge. Which makes zero sense to me on how it could still pass information.

I just watched CycloneFPV's video (link added below for reference), but just removing the diodes without replacing them or bridging the contacts doesn't seem to make any sense. He did mention in the video that he got interrupted a few times with phone calls so maybe an important part of the video got inadvertently cut out where he added solder bridges where the diodes had been. I did try to see if there were any obvious "jumps" in the video but I couldn't spot any. Unfortunately we can't see the board of the Vista in enough detail to see if any solder bridges exist before the re-assembly was done. It might be worth firing an email to Tarek asking him for clarification. If you do manage to find out can you please post the information back here. 

(15-Apr-2021, 06:29 PM)SnowLeopardFPV Wrote: I just watched CycloneFPV's video (link added below for reference), but just removing the diodes without replacing them or bridging the contacts doesn't seem to make any sense. He did mention in the video that he got interrupted a few times with phone calls so maybe an important part of the video got inadvertently cut out where he added solder bridges where the diodes had been. I did try to see if there were any obvious "jumps" in the video but I couldn't spot any. Unfortunately we can't see the board of the Vista in enough detail to see if any solder bridges exist before the re-assembly was done. It might be worth firing an email to Tarek asking him for clarification. If you do manage to find out can you please post the information back here. 

Thanks for the information! I actually reached out to Tarek and he immediately replied.
"It works without bridging - just make sure you have a good capacitor on the quad"

I'm going to give it a go today and I'll be sure to report back.

(16-Apr-2021, 01:27 PM)BunkrdU Wrote: Thanks for the information! I actually reached out to Tarek and he immediately replied.
"It works without bridging - just make sure you have a good capacitor on the quad"

That's interesting. Thanks for posting the info. I assumed the diodes were inline with the TX, RX, and SBUS lines but they clearly aren't if the serial communications still work without them even being present on the board, so I wonder what they actually do. I would love to be able to see the circuit schematic.

(16-Apr-2021, 02:29 PM)SnowLeopardFPV Wrote: That's interesting. Thanks for posting the info. I assumed the diodes were inline with the TX, RX, and SBUS lines but they clearly aren't if the serial communications still work without them even being present on the board, so I wonder what they actually do. I would love to be able to see the circuit schematic.

Just completed the removal and I can confirm it fixed my issue without bridging or replacing.

(16-Apr-2021, 03:51 PM)BunkrdU Wrote: Just completed the removal and I can confirm it fixed my issue without bridging or replacing.

I had the same situation as OP, had OSD then lost it after a crash in which the ground lead separated from the vista unit's pad.
Went through troubleshooting for no OSD before removing the RX, TX, SBUS diodes from the Vista unit. I still get a picture now, but no OSD (and it's still stuck in low power mode.)
Went as far as resoldering all connections between the Vista and the FC with brand new wire but no difference.

Before:


After (was a bit of a struggle to direct the hot air gun and grip w/tweezers, hence the ugliness):



FC is a Xilo Stax F4 (BF target GEFP/XILOF4(STM32F405)) https://www.getfpv.com/xilo-stax-f4-flig...oller.html
UART3 is configured for Serial Rx (Happymodel ELRS 900MHz)
UART4 is connected to vista unit MSP, 115200, soldered to physical pads marked TX4 and RX4 on the board.
Nothing connected to SBUS on the FC or the vista.
Vista was connected to VBAT directly, the only cap providing filtering was between the battery leads.
Running on 4S.

I must have missed something here, that or I really messed the Vista unit up lol.

I recently had a problem Not receiving OSD information while I did have video signal on my Babyhawk II HD. 

The solution:

I replaced the ESC and had my OSD back. Turned out it had nothing to do with my Caddx Vista. 



However.... a few sessions and 10 packs later I'm actually having a problem with my Caddx Vista having very low signal. I get 1 bar holding it in my hand. 
  

I've tried 3 brand new antenna's no luck, Tested with 2 different pairs of DJI vs goggles - same issue. 

Re-soldered with new wires. refreshed software update. 

Its not auto temp control... nothing changing after arming or disarming. 



All this with no luck...

(11-May-2021, 09:33 PM)surflick Wrote: I recently had a problem Not receiving OSD information while I did have video signal on my Babyhawk II HD. 

The solution:

I replaced the ESC and had my OSD back. Turned out it had nothing to do with my Caddx Vista. 



However.... a few sessions and 10 packs later I'm actually having a problem with my Caddx Vista having very low signal. I get 1 bar holding it in my hand. 
  

I've tried 3 brand new antenna's no luck, Tested with 2 different pairs of DJI vs goggles - same issue. 

Re-soldered with new wires. refreshed software update. 

Its not auto temp control... nothing changing after arming or disarming. 



All this with no luck...

^bump on the 1 bar problem. I get OSD. But after about 5 flights on my new vista unit I no longer get more than 1 bar. I've TRIED everything including swapping it out for a known good vista which worked perfectly fine. Anyone have an idea on a fix for the horrific range issue?

(02-Jun-2021, 05:31 AM)fruition Wrote: ^bump on the 1 bar problem. I get OSD. But after about 5 flights on my new vista unit I no longer get more than 1 bar. I've TRIED everything including swapping it out for a known good vista which worked perfectly fine. Anyone have an idea on a fix for the horrific range issue?

^bump.

Looks like my problem: https://intofpv.com/t-sporadic-caddx-reception-problem

Hey Is the issue fixed for you ?


I am facing an issue where the bitrate drops to anywhere between 0.5mbps to 30mbps from 50mpbs as soon as I arm the quad. Everything was working fine previously and today midflight (casual flying low throttle) within 5 seconds the bitrate dropped from 50mbps to 1 Mbps and the goggles video froze. After disarming and crashing the video was back but when I armed again the bitrate was like 2-5mbps and I barely flew it back.

Now, whenever I try to arm the quad the bitrate drops from 50mbps (unarmed) to 0.2-0.5 Mbps (armed) within a second, and the video breaks. Even when I try to use the motor beeper while disarmed the bitrate drops. Everything seems to be working fine when the quad is unarmed and the motors are not spinning or beeping. (After doing some throttle punches without propeller this issue of beeper reducing the bitrate got fixed idk how)

I tried opening everything up and cleaning and checking for grounding and found no issue but the problem is still there. The capacitor is mounted properly and the VTX works fine when unarmed. I have tried connecting the VTX directly to the battery but the issue persists.

What could be the issue and how to fix it?
Specs - F55A Tmotor ESC, F7 Tmotor FC, Caddx Vista Nebula Pro VTX