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relee

extreme a/v noise @ heli cam

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@ Mr. RC-CAM

Sure, as long as you correctly install a mating SMA connector on the Tx.
What does this mean? :blink: In a digital world (with 0's and 1's) that just tells me: solder the SMA connector instead of the existing antenna: ...use the existing ground as the ground for the SMA connector and the existing "signal" for the SMA signal ... is that right? Edited by relee

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Funny you should say that, I just watched your video and was going to ask for a longer clip, all it reminds me of is a microwave oven. Were you warming a meat pie at the time ?

Terry

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The clock is fast heading to midnight here so I will have to look in the morning, good luck.

Terry

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In a digital world (with 0's and 1's) that just tells me: solder the SMA connector instead of the existing antenna: ...use the existing ground as the ground for the SMA connector and the existing "signal" for the SMA signal ... is that right?

In a purely digital sense, you've nailed it. In the evil analog reality, there are many ways to make a mess of this seemingly simple task. It's microwave RF; at 2.4Ghz, the little details matter. So, be very careful to observe the connector mfg's termination instructions.

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OK, I just watched both video's. It seems to me that I can see 2 problems. The first is that the video is looking like a weak signal even when quite close in. I would first change the TX aerial to a whip or duck type that has a clear veiw from under the heli. The other is the interference which is not constant pointing to an external source or may be from the heli but only shows when the poor aerial is causing a weak signal anyway.

Can you confirm an onboard problem by repeating your walk test just after or before a test flight.

You would also do better by using patch type aerials on your RX.

Do you have a fixed wing aircraft you can test fly the video gear with at this site ?

Terry

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Seems like extreme external interfecence to me. You might not have a phone or wifi there, but there could be a transmitting tower, or radioamateur in the neighbourhood transmitting at incredible power levels,...

I'd try at another location. What happens if you go and put the heli on the ground 200m away from the RX, and leve it alone (stopped)? When you land you're always close and the video signal is stronger, but as soon as you go a bit further, it gets overwhelmed.

The thing is that both the static position and sound seem to suggest there's a mains frequency component there.

Are you maybe using a power inverter to power your ground station? These things can send serious spurs. The dirty mains-frequency tone in the sound at least looks like what it could cause.

Edited by Kilrah

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Changes:

1) soldered the 4 corners of the Tx chassis

2) moved the Tx from the alu stand-up to point downwards (this made the antenna stick "ouside" the heli)

3) chaged the setup of the cam from 2 screws to my old setup: a bit of foam on each side & cable ties B)

Next I went to the same spot again and did the distance check .... but this time with the heli :angry: (quite heavy after a while). When I came back and checked the recording: crystal clear :lol:

So with good hope, I put the main battery in and started the engine .... :angry: again this terrible noise.

Stopped everything and took the heli really close to my hearth ... I couldn't believe it .... how could this be?

Took me a while to figure it out:

1) the cut audio cable was still causing way too much noise - so I simply ripped it out of the Tx (thanks for the "ghost" audio hint Mr. RC-CAM)

2) the screw to hold the cam stand-off was about 1 mm too long - so that it touched the chassis of the Tx - a slice of paper between the screw and the Tx chassis fixed that

Did a couple of runs today ... and happy as a clam :D

The VIDEO isn't just that great .... but I sense that this is due to my cable between the cam & Tx. I've already received spare parts to build a new one.

PS: actually I also made sure that all mobile phones are OFF + disabled the Bluetooth from the car. BUT there is a very large GSM (mobile phone) receiver station in the distance of about 1 1/2 km.

Many thanks again,

relee

Here is my new setup - maybe it helps someone else in the future.

post-5-1191345425_thumb.jpg

Edited by relee

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the screw to hold the cam stand-off was about 1 mm too long - so that it touched the chassis of the Tx - a slice of paper between the screw and the Tx chassis fixed that

I thought you had isolated the Tx by mounting it with foam tape ?

Good news though :)

Terry

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Yes Terry I did - but only towards the left side (back) - since by design (5 mm) it wasn't touching the top .... but then the screw came :o

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