[TowerTalk] radial lengths ...

[StellarCAT]

For the ‘experts’ out there ... 

So question.... in ON4UN’s book it is stated in abundance that one should use typically 0.25 wl radials... the length of course varies with the properties of the earth and the desired end results but somewhere around 32 1/4 wave radials seems to be within about 1 db of 100+ of the same length ... 

but he also states, kind of “on the side” in one sections only (it seems) due to the velocity factor attributed to the earth that 1/4 wave is actually physically only 0.14 waves in length! 

So which is it – when it is stated 32 1/4 wave is that physically 1/4 wave or is it physically say 1/7th wave (and still electrically 1/4 wave)?! 

so for example on a 160 meter vertical are we looking at 32 ~130’ radials or more like 75’ radials (with the end of each of those not having enough current in them to contribute appreciatively to the current distribution)... ?

I know most will respond with 1/4 wave.... but I’d bet most would be going by the generic statements of “1/4 wave radials for verticals”... if indeed the VF makes going beyond about 1/6th wave of very little value (again talking about 32 radials here – not 120) ... then why go through the effort? 

if this is (more) clearly stated in John’s book please let me know where. 

Gary 
K9RX