This calculator will give you an idea of how well a given coaxial cable type will perform for a given frequency as compared to other types at the same frequency. It is not a guarantee of performance, just a guide to what you can expect so you can decide if it's worth spending a few extra pounds on your instalation (don't forget to factor in the cost of any "special" connectors that you may require too!).
Where more than 1 manufacturer supplies a particular cable (ie the "RG" range) I have taken figures from several suppliers and averaged out the figures for same type for use in this calculator. Manufacturing tolerances mean that any quoted figures are, usually, "best case" or "average" and are not guaranteed (plus there is a huge variance in manufactured quality, one particular instance springs to mind when a friend of mine asked me how to clear up the TVI he was giving to his neighbours. After I examined his set-up and replaced the coax all was well with the neighbours. Why? Well the "braid" of his coax, which was labelled RG-58 and was around the going price for "decent" '58 at the time, consisted of just a few strands of copper which were in no way shielding the signal! I hate to think what losses were involved.).
If there is a type of coax that you would like listed or another band you wish to see added then let me know at the usual address (brian.mw0gkx@ntlworld.com) and I will track it down and add it (if I can).
To use the calculator just enter the length (in meters) in the Length box and click on the Calculate Losses button. If you wish to check a different length then just delete the contents of the Length box and start again