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By: Hugh Sherborne
Date: 31/07/2008
When choosing a wireless camera, it is important to analyse your requirement.
If you want a covert camera, which can be hidden easily, the Mini Spy Camera is ideal. It only needs a 2mm hole for the lens to see through, and can be powered for a short time by an ordinary 9volt battery. For a longer time, it can be powered by the mains adapter supplied.
The camera can transmit for up to 80 metres, as long as there are no obstacles between the camera and the receiver. In practice, normally there are obstacles in the way, and it is important to position the camera and receiver properly to minimise these. A solid wall can reduce the distance to about 10 metres, and if there are 2 solid walls in the way, it may be difficult to receive a signal at all.
This camera is ideal if you need to mount it outdoors, and if you want night vision. It has a 3.6mm fixed lens, which gives a 65 degree angle of view (see our lens field of view table - It also has infrared LEDs which can see for up to 15 metres in the dark. (Infrared vision is in black and white).
Again, it is important to choose the postition carefully, to minimise any obstacles in the way.
This camera is ideal for applications where long transmission distance is needed. It will transmit for up to 400 metres, as long as the antennas are in line of sight.
Because is has a more powerful transmitter, it is can also be more successful when there are a number of obstacles to be overcome, but the distance is still reduced by blockages in the way.
This camera can be used outdoors, but it has connections on the back of the transmitter box, which need protecting, usually by sealing with silicone.
All our wireless cameras use the same frequencies: 2.414Ghz; 2.432Ghz;
2.450Ghz;
2.468Ghz.
This means you can only use a maximum of 4 cameras with a receiver, or they will interfere with each other.
Also, the receivers are switching receivers - that means that they receive only one channel at a time, and can either switch automatically between frequencies, or can be set to stay on one channel at a time.
Consequently, if you want to record from your cameras, you need a receiver for each camera, so that each camera/receiver can be set to its own channel. One problem with this, is that if you have more than one receiver close together, they can interfere with each other. That is why we recommend a maximum of 2 wireless cameras with all of our DVRs. With 2 receivers, you can set them at say channel 1 and channel 4, and keep them as far apart as the cables will allow, and the interference is minimised.
General Information
With wireless cameras, the picture is never as steady as with a hard wired camera. Wireless cameras are subject to interference, atmospheric conditions, and signal drop out. Having said that, they are very useful in the right conditions, and sometimes thay are the only solution.
If you are in any doubt, please contact us for advice.
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