I have added the ability to include a known velocity factor into the Slim Jim / J Pole calculator, to help with building them with 450Ω or 300Ω feeder. Also, here is a tested and reproducible Slim Jim for 70MHz (4m) made with 450Ω balanced feeder:
70MHz Slim Jim constructed out of 450Ω feeder
Thank you for help with your projects! 73!!! PU2MAL
Thanks john.. and i like it. 73
I have a sizable collection of Mitsubishi 10W power amplifiers tested over 70cm at full power type M67799HA for sale very cheep
great site, a lot of info available I like the resonance calculator