I was looking for coax to replace the Quarter wave transformer in a commercial VHF Folded Dipole Antenna.

Calculations for coax required to match 300 ohms to 50 ohms revealed that a coax with an impedance of approx 120 ohms is required.

Z= √300 x 50   equals 122 ohms. RG63 has an impedance of 125 ohms and will be the obvious replacement.. but can you find a place to buy short lengths?

I couldn’t ….But in my search I found this

http://ve2azx.net/technical/CustomImpedanceCoax.pdf

 

Thanks VE2AZX and VE2BPD