[Antennas] How to calculate cable length

[Charles E. Pitts]

Hello all, I am requesting help in calculating the amount of cable length in feet that I have from catv cable reel ends.

I have numerous rolls of reel ends of both insulated (burial) and non insulated (aerial) catv hardline that I plan on using primarily for HF work.

I have heard somewhere and I can not remember from where or from who that if you count the number of turns and multiply that times the diameter of the actual spool you can get an approximate amount of feet remaining on spool?

Is that correct or does somebody out there who has had a similar situation and has encountered an unknown amount of cable, etc. have a more definitive way of determining the amount of cable or wire one may have that is on a spool?

Unfortunately I have no access to equipment that may help me as I am in the process of building a new home and establishing my future antenna farm and getting ready to pull the cable I have to the tower site, etc.

Some, if not most of the insulated cable I have on hand has had the #'s faded  which may tell you on the spool the # of feet left, and is unreadable and is of no benefit.

Thus the reason for me finding out another way of calculating the # of feet remaining.

Thanks in advance for all responses, Ed K5OF in NC