2.4 GHz Video Link

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2.4 GHz Video Link Experiment.

The experiment was to establish the usefulness of a standard Video Link working at 2.4 GHz.

The unit evaluated was the Philips Wireless TV Link model SBC-VL1200. The unit was kindly supplied by Philips Accessories for our evaluation.

The Transmitter used a rather large battery for the job, placed into a small Laptop case. A Philips universal car adapter was used to convert to the 9v needed to power the transmiter unit. A standard scart to phone adaprer was used from the camera.
The transmitter has 2 video scart inputs and so 2 input sources could be used at an incident. Both inputs also have a monitor out for local monitoring.

A standard Sony video camera was used taking video and audio out to feed the camera into the the Transmitter. Both audio and video can be transmitted over the link.

The Transmitter was held in a video case being carried by Ken M0XGB the intrepid cameraman. The Video link aerial can be seen sticking out of the camera case.

This is a view of the test site which is a large park behind G3VPA's QTH.
The transmitter operated easily at 150 metres and with some intermittant breakup up to 170 metres.

This was with the Receiver on the roof of a car and the handheld case at only 2-3 foot off the ground. A greater distance may have been possible placing the receiver on the roof of the mobile control vehicle.

This shows the receiver unit sitting on G3VPA's car roof. A waterproof bag could be used in case of rain!

The Result.
A standard TV with scart input was used for the test. The TV and the receiving Video Link was powered by a small Power Sciences DC-AC 120W inverter working off of a 12 volt battery in the boot.

A closer view of the received image.
The tests proved that a local video link could be put together very easily to give a full bandwidth colour video link over a distance of 150 metres from an incident site. Two camera feeds would be available at the incident with the possibility of remote control being sent over the 2.4GHz link.

The next stage is to fit an external aerial socket, add a 1 watt amplifier and 19dbi gain aerial to increase this distance.

A view of the Transmitter shows the 4 scart sockets for 2 inputs, and 2 monitor outs. The LCD's at the front are Power and infra red, Any infra red remote control is also carried over the 2.4GHz link and so could be used for remote video switching or camera control at a non-secure site.

A closer look at the aerial feed This could easily be converted with an SMA socket to feed a 1 to 5 Watt amplifier. There are 4 channels available which fall into the amateur band so higher power output is legal.
The plan is to feed a 1Watt amplifier into a 19dbi aerial to give approx 80W eirp.

The receiver will stay the same in test 1.

Test 2 will involve adding an aerial to the receiver along with a preamp to overcome any cable loss.

More reports to follow.

--------------------------------------------------------------------------------------------------------------------------------------------------------------

Michael Rose G3VPA.

^^ Top ^^

Photographs Copyright © 2003. All Rights Reserved.

Copyright Medway Raynet.
Last revised: October 20, 2003

The Transmitter used a rather large battery for the job, placed into a small Laptop case. A Philips universal car adapter was used to convert to the 9v needed to power the transmiter unit. A standard scart to phone adaprer was used from the camera. The transmitter has 2 video scart inputs and so 2 input sources could be used at an incident. Both inputs also have a monitor out for local monitoring.
A standard Sony video camera was used taking video and audio out to feed the camera into the the Transmitter. Both audio and video can be transmitted over the link.
The Transmitter was held in a video case being carried by Ken M0XGB the intrepid cameraman. The Video link aerial can be seen sticking out of the camera case.
This is a view of the test site which is a large park behind G3VPA's QTH. The transmitter operated easily at 150 metres and with some intermittant breakup up to 170 metres. This was with the Receiver on the roof of a car and the handheld case at only 2-3 foot off the ground. A greater distance may have been possible placing the receiver on the roof of the mobile control vehicle.
This shows the receiver unit sitting on G3VPA's car roof. A waterproof bag could be used in case of rain!
The Result. A standard TV with scart input was used for the test. The TV and the receiving Video Link was powered by a small Power Sciences DC-AC 120W inverter working off of a 12 volt battery in the boot.
A closer view of the received image. The tests proved that a local video link could be put together very easily to give a full bandwidth colour video link over a distance of 150 metres from an incident site. Two camera feeds would be available at the incident with the possibility of remote control being sent over the 2.4GHz link. The next stage is to fit an external aerial socket, add a 1 watt amplifier and 19dbi gain aerial to increase this distance.
A view of the Transmitter shows the 4 scart sockets for 2 inputs, and 2 monitor outs. The LCD's at the front are Power and infra red, Any infra red remote control is also carried over the 2.4GHz link and so could be used for remote video switching or camera control at a non-secure site.
A closer look at the aerial feed This could easily be converted with an SMA socket to feed a 1 to 5 Watt amplifier. There are 4 channels available which fall into the amateur band so higher power output is legal. The plan is to feed a 1Watt amplifier into a 19dbi aerial to give approx 80W eirp. The receiver will stay the same in test 1. Test 2 will involve adding an aerial to the receiver along with a preamp to overcome any cable loss. More reports to follow.