Topband: capacity needed for Deturning tower

[terry burge]

Hi again,


This may not be possible to answer with anything like 10% accuracy but can someone give me an idea just how much capacitance I need for putting up a 50-55' vertical wire up the lower half of my tower to detune it on 75 meters around the DX windown (3790-3800 Khz). The tower is Rohn 55 with 117' above ground. A 3 element 20-6 mtr Steppir at 118', a GP6 at the very top with peak at 134' and a 40 meter dipole (63' or so) at 104'. I have my K8UR style 4-Square around the tower with the lower half of the slopers pulled in towards the tower. 


Since I've not been able to get a beverage or bog to work due to a lot of noise I'm going to run a detuning line up to below my Comtek unit at 64' and try detuning the tower. But I just don't know what to expect to need for capacitance to detune the tower. 


Terry

KI7M