There is a price to pay for the lightweight RG174 cable and that is in the power that your antenna receives20 metres, at what frequency?
If it is about 1.5dB down that means 1/4 of an S point at the other end.
73 Alan G4ZFQ
. For a 20 meter length of RG174 the
loss is 1.366dB so for 5 Watts output from your transmitter, the antenna will receive only 3.65 Watts. Compare this to RG58 where the loss for the same length is 0.611dB and 4.344 Watts will be delivered to the antenna.