As mentioned above these units use RP SMA connectors – so an adaptor is required to connect to the panel antenna which has an N type female. A RP SMA Male to N Type Male adaptor was acquired for a few pounds, again from eBay.
The TX unit does get quite hot when transmitting, even for short periods, so a piece of head sink was glued to the back of the unit to help with heat distribution. As nearly all ATV activity takes place outside the cooler surroundings also helps with this. A 12v fan to cool the unit may be added if required.
The TX unit was mounted in a case which allows for direct connection to the panel antenna. The units come with a lead supplied for power, audio, video and ground, making for easy connection. RCA phono sockets were added to allow easy connection of video and audio sources (the ground was added to the video source). As there is no obvious way of knowing if the unit is powered up (there's no LED or anything to indicate if power is on), so a simple LED was added to show that power, and therefore TX, is on.
A power lead comes from the bottom of the case and is plugged into the 12v power distribution unit - described in detail here.
As RCA phono sockets were added, this allows for different AV devices to be used. For ease and initial testing 2 small 12v cameras were used. Any video camera with a composite source will work and these have also been used.
I already had a 12v car reversing camera in a drawer in the shack so that was used initially and worked well, giving clear video signals. There were a couple of downsides to this camera, one being that it was video only, so no sound was possible and the other was that as it was a 'reversing camera' intended for a car it had red, yellow and green 'marker lines' that were transmitted. Not the end of the world, and certainly fine for testing purposes.
An added bonus was that the camera was waterproof, so ideal for using during winter !
Options for a new 12v camera seemed to be limited, and it always seemed to be a 'compromise' when finding alternatives. Another camera which was used offering the added bonus of sound, but only a black and white video signal. But again, the low cost (about £5.00 a camera) from eBay made it a suitable choice when trying to keep the cost of 'sundries' down. I also had an old Panasonic video camera (with AV outputs) which works perfectly.
These little 380 line PAL black and white mini cameras were brand new and feature switching infra red and have sound. The infra red LED's automatically switch on when light levels get low. They have standard AV connectors for audio and video and require a 12v power supply – a must as I wanted to power all the kit from one 12v distribution unit. The main body of the camera is just 35mm x 25mm x 15mm and they are fitted with a 3.6mm lens.
What the black and white video looses, the audio quality from these cameras more than compensates for. As these ATV systems are FM, the audio is just like any other FM signal – loud and clear!
As mentioned I also use a Panasonic video camera, which works alsoperfectly.
