Maybe try powering the GPS from the VTXs 5v out?
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There isn’t one. Not in an easily accessible ‘pad’ wise situation anyway.
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Oh yeah it’s a sharkbyte VTX. I forgot lol
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I’ll spend 1 more evening on it, then I’ll just fuck it off.
It’s not like any of you guys will beat my speed record anyway 
See. Your the boss! 
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Have you got the capacitor fitted to the VTX board?
Is it better, worse, or the same with VTX in low power mode?
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Its the same what ever power level its at. And I have the cap on the main supply. Its there to stop spikes? I can try another direct to the vtx…
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As a fault finding exercise can you power up the GPS from an external 5v power supply (not attached to your quad) just to eliminate the possibility of a voltage issue?
At least then you’ll know for sure that its RF interference from the VTX and not a power issue.
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First step is: I’m going to shield the gps wires. They could be acting like an antenna picking up noise.
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Unlikely, they are a TTL (or similiar) signal, carrying the UART signal. I’ve never had an issue with those, unless of course I do someat daft and connect them wrong, then they never work 
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That is strange, 
Does the mag work? but you’ve probably not got it connected for BF Rescue
Have you double checked that you’re using correct RX,TX pads and that CLK and DAT are not connected at all?
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This leads me to believe it’s not RF interference from the VTX but noise generated by the digital circuits. If the Shark Byte has a Pit Mode engaging this could confirm it.
If the interference is being induced by the cables a simple way of reducing it is to twist the cables. I do this on all my builds as it reduces the possibility of the cables radiating interference. This principle has been in use in telephone landlines. The telephone lines, like the cables used to connect drone peripherals, are unbalanced where RF is concerned and are prone to radiating. To reduce this phenomenon the telephone lines are twisted, hence the term “Twisted Pair”. The theory behind this is that twisting the cable results in the signals on each wire being close to 180 degrees out of phase with each other and thus near cancel out the unwanted radiation.
The copper foil method is also a good one to try. Many off the shelf drones incorporate this technique for the very same reason. One that didn’t was the 3DR Solo which was renowned for lousy GPS acquisition, and the 3DR Solo I bought off eBay earlier this year was no exception. I made my own screen with copper tape, using the cardboard separator that electrically insulated the GPS unit from the mainboard as a template, and the end result was a much faster GPS acquisition and a decreased HDOP value. You could 3D print a simple box for your GPS unit, line it with copper tape, or any other non-ferrous metal in case you’re using a GPS with compass, and this will hopefully reduce the induced interference from the SB transmitter.
HD video systems have a long history (if 10 to 15 years is considered history?) of problematic interference issues with RC electronics. Back in the day, when 433MHz was the defacto long range system, the Möbius and GoPro cameras were synonymous with interference. Many would strip the cameras and use foil or electrically conductive paint on the inside of the cases to reduce interference from the cameras fast switching A/D circuits.
I see you subscribe to the Shark Byte Facebook group, Karl, so if you haven’t already done so I would also pose the question there. There is a higher probability of users with a similar setup to yours on there. I would of also suggested the FPVHUB website as Fatshark had their own manufacturer thread on there but the site seems to be no longer active even though it’s still viewable.
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@notveryprettyboy I threw this together in tinkercad do you want the STL file to adapt to your requirements?
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I put a cap on the vtx power input. No change.
I used a 5v bec for the gps, no change.
I stripped some tv ariel wire for the copper sheath and put it round the gps wires, and I got some improvement. So I made a proper cable up. I can get 6 sats in the garden now, armed or not. But I have had this before - it’s worked, then not worked (@Steviegeek knows!)
If this method works, I’ll buy a proper shielded cable.
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Jees, you’re learning that fast!
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You have no idea 
I done 4 years of mechanical and production engineering at college before finding my fulltime job as a printer engineer lol
I’ve got a city&guilds in mig and tig welding and a btec in milling and turning. It’s just been many years since I done any of it lol but working with drawings was a big part of my college work so I had a bit of a head start
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Mine is running at 57kbits. If there is noise close to this, could it affect it? Wish I had a decent spec analyser now!
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Hold that thought. I’ll detail my poor man’s solution when I get to my PC.
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