Good Afternoon,
I am planning on moving my antenna from my garden fence and relocating it to the top of my roof.
Below is the connection at the dongle end (hope its clear enough). IS it possible for me to purchase 10-20mtrs of coax with the correct connectors to simply extend it? I cant do anything at the antenna end as its a custom built ADS-B antenna and its all sealed up.
Thanks in advance
Yes you can do that, be aware that a longer cable also introduces more loss of signal.
You will need a SMA male on the SDR side and a SMA female on the antenna side ( providing you connect to the original antenna cable).
You could see how it goes and if it degrades too much you could opt for adding an LNA to improve the signal.
As above, but be aware SMA’s are not weather proof, so if exposed, will need sealing.
@davewill2010 as tomvdhorst says, extending the cable is very likely to introduce more noise into your feed, as well as attenuating the signal. Furthermore, SMA connectors are anything but waterproof, so you’d need to use a waterproof plasic box, with bottom-entry glands for the cables to prevent water ingress.
One thought, however, how about bringing the antenna cable into the loft, either under the eaves or via a hole in the brickwork, fitting the receiver in the loft, then bringing the USB cable to the Pi (or whatever) internally - or even having the Pi in the loft as well, connected via wireless - that would then only need a 240Vac power feed for the Pi, this would eliminate the hassle of extending the antenna cable at all.
Hi Tony,
Now the loft install is a much more tempting idea then me sliding around on the roof installing the antenna! Will I lose much signal moving from an external location to an internal location ?
Thanks in advance
I was thinking about that. Yes, you will lose some signal, especially if inside the joists has “chicken wire’“ to prevent bird access, and/or the area is insulated with a foil-lined foam for heat retention. Given what you’re looking to do, I’d still go with putting the antenna on your tv mast (which is what I’ll be doing with mine), then feeding the antenna lead into the loft space (remember to put some tape over the end of the SMA when feeding the end through the walls). Using this approach, the antenna has a 360 degree unobscured view of the sky, thus maximising your range.
Research has been carried out on this previously - see How much better is an external antenna?