This JavaScript program evaluates the performance of an antenna system, computing the consequences of SWR and feedline loss.
original program concept done in CPM basic by KC6A and N6NB

forward power from transmitter in watts -1VSWR @ transmitter
feed line loss in db( must be in line with other values)  Enter 2.2 for dipoles; add 2.2 for antennas rated in dBd 
Enter operating frequency in mHz 1.8mHz to 2450mHz

reverse power at transmitter -1VSWR @ antenna
forward power in watts at antenna reflected power in watts from the antenna
true power in watts into antenna power in watts lost in feed line
db line loss including EIRP in watts power in watts off the antenna

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