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Are FPV tablets the answer to wireless video monitoring?

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#1 Charles Copeland

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Posted 14 August 2014 - 06:02 PM

FPV means "First Person Video" and is used for video transmission from personal drones.

 

I've been trying to figure out how to go totally wireless with astro video astronomy.  Orion has the WiFi RS232 devices for control, but wireless video seems to lacking options.  I stumbled onto the new 5.8gig FPV 7" tablets used for drones.  Seems the price is very low, but not sure about the video quality.  Would this work with acceptable quality for astro video?

 

You can see many on ebay if you search for "5.8G FPV Monitor". 

A 5.8gig wireless video transmitter and FPV 7" tablet with built in receiver are as little as $150.

The transmitter takes composite video input and so can be used with any astro video camera.

 

Is this the best solution?  Is anybody using these for astronomy?  Is there a better WiFi solution at this price?

 

Ideally it would be great if there were a  WiFi box that transmitted several video and control (rs232) channels, but have found none.


Edited by Charles Copeland, 14 August 2014 - 06:05 PM.


#2 guyinthesky

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Posted 14 August 2014 - 06:51 PM

hi, i use an ordinary inexpensive wireless video sender, it works well. there are lots of them on ebay. i did a test with the sender vs a cord and there was only slight degradation with the $39 video sender. i am not sure how far away you will be, some transmit a few hundred feet.



#3 ccs_hello

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Posted 14 August 2014 - 10:03 PM

Over the years, people tried on various forms of wireless video transmitters. About 10 out of 10, the cheaper ones be a 2.4 or 5.8GHz type, require an operator's license from FCC.
In another word, these are not gold mines.

Low power ones may be "below the radar". High power ones (marketed as long distance) are bad idea.

Edited by ccs_hello, 14 August 2014 - 10:39 PM.

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#4 Charles Copeland

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Posted 15 August 2014 - 11:44 PM

I like the idea of having a receiver built into a 7" tablet, but they are paired with high powered transmitters for drones that require a license.  

Perhaps that tablet could be paired with a low powered 25mw 5.8g "video sender" transmitter guyinthesky mentioned?  


Edited by Charles Copeland, 15 August 2014 - 11:45 PM.


#5 ccs_hello

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Posted 16 August 2014 - 04:47 AM

They are not "tablets" as people would have called. They are 7" LCD monitors with built in AM wide band receiver(s).

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#6 ccs_hello

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Posted 01 October 2014 - 08:30 PM

Add some info on FCC Part 15 "Low Power" regulation

http://transition.fc...63/oet63rev.pdf

 

Foe example, I found a 5.8GHz analog FM video modulator and transmits at 0.37 mW (I think it is, FCC submission says 93dBuv/m @3m <-- almost hit the limit at zero margin

and < 1mW RF Power.)  

This gadget has a 3dBi integrated antenna and is a low power Tx with 100 meter line-of-sight.


Edited by ccs_hello, 01 October 2014 - 08:58 PM.


#7 core

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Posted 02 October 2014 - 03:27 AM

I've been using $18 TX/RX pairs meant for vehicle backup cameras (amazon, ebay, etc - search for 2.4Ghz Video Transmitter) on my various setups; I believe it should work equally well with CCTV LCD monitors that have built-in 2.4GHz video receivers (which would mean one should be able to transmit and receive multiple video streams, and with some of these LCD's have built-in DVR capabilities).  I've not looked into 5.8Ghz sets just because of their comparative cost, and the 2.4GHz setup have worked well for me.

 

Plugging in SkyFi to the mount makes for a nice wireless setup.  First picture show the 2.4GHz TX in my most compact astro-video setup.  Second picture is for lunar eclipse imaging session; I can track the progress of the eclipse from the comfort of indoors if needed, and can trigger the DSLR remotely (latest DLSR/Mirrorless have almost complete WiFi control of the camera, including live video feed).

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Edited by core, 02 October 2014 - 03:31 AM.


#8 Charles Copeland

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Posted 02 October 2014 - 10:41 AM

The 2.4gig units on ebay seem to have limited bandwidth as none state they can support 750x480 resolution. 

Do you lose video quality with these 2.4gig units?

 

The FCC power limitation is confusing as I've seen 5.8gig "video senders" advertised for 10mw or 20mw and legally sold.  The 200mw PV units require ham license. I'm not sure of their video quality or range. Here is one on amazon.  Seems the 5.8gig units cost double the 2.4gig, but should be more immune to noise and high res.

http://www.amazon.co...FH0QW1VCAXJ9X1W


Edited by Charles Copeland, 02 October 2014 - 10:41 AM.


#9 Larry F

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Posted 02 October 2014 - 11:27 AM

I have the Terk LF-30S and used it last weekend to broadcast a short distance (15') from scope to a laptop with (cheap) video-USB adaptor. I think the adaptor degrades the signal more than the transmitter/receiver combo. It's a little more expensive ($62)than the cheap tx/rx units that are in the $35 price range but I had one of those and it was, frankly, pretty bad, with a lot of interference in the signal. They also make extenders if you need to pass the signal for a longer distance.

 

It's a good tool for outreach so you can avoid any wires on the ground that can be snagged in the dark.



#10 Hilbily

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Posted 02 October 2014 - 11:55 AM

I wonder if these wifi ones will work, then I wouldn't have to get a monitor?

 

http://www.ebay.com/...sd=121439954900

 

http://www.ebay.com/...=item4187074fa0








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