Wireless video

[mac.calder]

I am working on a production at the moment (still in the very early planning stage) and we want to have one of the actors with a video cammera (I have a relatively good (large) camera which takes full size VHS cassets, to reduce 'wobble'), and beam the images to two projectors (or more, depending on budget) WITHOUT wires between camera and mixing desk. Main reason is the current set design has a lot of poles, and since the chances are the actor will be weaving through them, it would be tedious to get the actor to backtrack.

 

I have contacted our regular hire places, they came up with nothing in their stocks.

 

The main requirements for the transmitter/recievers would be:

 

Cost - the number one factor. The less the better.

Range - at least 50m is needed.

Frequency - it is not allowed to interfere with a number of wireless mic's being used - so freq. selectable is best.

Connectors - RCA or Coax plugs

Size - beltpack or smaller. Direct mounting on the back of the camera would also be fine.

 

I am in Australia, so mentioning hire companies etc in other countrys is no good.

 

I know it can be done (a local cabaret restaraunt does it during interval, a roaming 'talk to the audience'), and I have a 2.4gHz device which is mains powered that does it, I have seen a camera that will do it, but I have not seen a battery operated add on.

[Freddie]

You could use a mini wireless camera built in to a prop, or gaffered to the side of the VHS camera. I'm on about the tiny ones that'll run for 6hrs of a PP3.

 

Or have you tried asking the restaurant where they got their's from?

 

EDIT: I dunno if Maplins will deliver to AU, bu they've got this, very very very small transmiter, and super mini wireless camera

[Tomo]

Does your existing unit use an external PSU?

If so, you should be able to swap it for direct DC power from a battery.

 

Either way, 2.4GHz units are the way to go.

 

If you can find a digital one, you'll get a better picture at long range and less interference from other things in the band, such as WiFi etc.

However, they are *very* expensive and so probably out of budget.

 

I have a pair of the miniature 2.4GHz transmitter units that zaphod mentioned, and these give me an indoor range of around 30m before the image starts to deteriorate.

(100m is the clear-air range - you'll probably never get anywhere near this)

They run from 12v DC, and are very happy to run from small SLA batteries.

 

A search of your local electronics retailers for 2.4GHz video senders should find something of use if Maplin won't deliver.

 

With regards to range, can you not put the reciever(s) on stage and use real cable from the wings to the mixer?

50m is a pretty tall order inside a building, assuming you want to stay licence-free.

[Locksmith]

I dunno if Maplins will deliver to AU, but they've got this super mini wireless camera

<{POST_SNAPBACK}>

 

ebay appears to have a similar item much cheaper, but I'm not sure about shipping to oz.

[tonymaslen]

I've just done a google on google.au.com, searched for "wireless camera 2.4ghz"

which gave me this link

 

hope it helps

 

 

I dunno if Maplins will deliver to AU

No not a the moment, maplin don't currently deliver to AU!!

[mac.calder]

You could use a mini wireless camera built in to a prop, or gaffered to the side of the VHS camera. I'm on about the tiny ones that'll run for 6hrs of a PP3.

 

Or have you tried asking the restaurant where they got their's from?

 

 

The major problem with the mini things are that they have relatively sh!t quality. These are being projected onto a large screen - crappy quality, magnified to a large screen... ICK!

 

Does your existing unit use an external PSU?

If so, you should be able to swap it for direct DC power from a battery.

 

Either way, 2.4GHz units are the way to go.

 

If you can find a digital one, you'll get a better picture at long range and less interference from other things in the band, such as WiFi etc.

However, they are *very* expensive and so probably out of budget.

 

I have a pair of the miniature 2.4GHz transmitter units that zaphod mentioned, and these give me an indoor range of around 30m before the image starts to deteriorate.

(100m is the clear-air range - you'll probably never get anywhere near this)

They run from 12v DC, and are very happy to run from small SLA batteries.

 

A search of your local electronics retailers for 2.4GHz video senders should find something of use if Maplin won't deliver.

 

With regards to range, can you not put the reciever(s) on stage and use real cable from the wings to the mixer?

50m is a pretty tall order inside a building, assuming you want to stay licence-free.

<{POST_SNAPBACK}>

 

The thing has an internal PSU, and looks like half of a model UFO... I was thinking beltpack... As for shoving the receivers in the wings, I am thinking that may be the only option. I just wanted to avoid sending the signal down a long length of cable to the bio box, specially since there is no real room for the cabling run available unless I send it down the audio lines (I have adaptors to change the RCA plugs to the 5.25mm plug, although IIRC they will end up going through a DI box and come out in an XLR plug at the bio box, so I will have to make an adapter I suppose)

 

I've just done a google on google.au.com, searched for "wireless camera 2.4ghz"

which gave me this link

 

hope it helps

 

Um... it's a uk place, but they look good.

[tonymaslen]

Um... it's a uk place, but they look good.

well this was a bad example! It stared out being a link from an AU sight but they do deliver to AUZ if you need it quick it does not say how long it would take to get to you about 3 weeks I guess!!! unless its FEDEX or some other courier.....

[J Pearce]

Would I not be correct in saying that a DI box would render the signal useless as it has too high an input impedance ie typically 1Mohm not the 75ohm standard for video.

 

Video will carry fine down balanced audio lines, just send it down the hot and cold cables leaving the screen disconnected. But DON'T send it through any audio gear just the cable.

[david.elsbury]

Video will carry fine down balanced audio lines, just send it down the hot and cold cables leaving the screen disconnected. But DON'T send it through any audio gear just the cable.

<{POST_SNAPBACK}>

Pardon? I don't think so. Starting from the top...

Video may carry fine down balanced audio lines. The cable impedance is wrong, it's running right next to audio lines, which may affect it, or it may be affected by the audio signal. Plus it depends on the type of the cable.

Don't send it thru the hot and cold cables, leaving the screen disconnected. This will open up the signal to any number of sources of interference. The screen is there to keep the nasties out! So in this case I'd wire pin 2 video hot, with pins 1 and 3 the video shield.

A better solution, if you must use the audio cable, is to use a balun at each end (CAT-5 ones could work here). Or you could just use coax. Pretty cheap as cables go.

*Disclaimer* I have indeed run video thru mic cables, and at times it worked 'okay' at best. But the last time I did, all the colour information dropped off due to distance and the wrong type of cable. Not good.

 

Regards

David

[J Pearce]

Sorry found guilty of being asleep when posting!!

 

As mentioned above the screen should be used to prevent interference.

 

Sorry if I ruined anyone's show!! :P