[Elecraft] High SWR problem

[Edward Kenworthy]

I suspect that's the problem - the wire is 20m long and I'm on 14MHz... I'll
try another band tonight and see what happens.


On 17/8/03 11:32 pm, "Vic Rosenthal" <vic@rakefet.com> wrote:

> Edward Kenworthy wrote:
> 
>> The ATU manual says, in essence, my RF earth is crap. 1 rod and using
>> braided is bad idea it says. OK fair enough, but isn't the point of a long
>> wire that it's easy - if I have to install an ultra-efficient earth system
>> with multiple rods etc then that rather defeats the point.
> 
> Yes, that type of ground is worthless for RF, but that is not the cause
> of your being unable to load the antenna.  Assuming that all the
> connections are OK, the wire may be presenting an impedance that is out
> of the range of your tuner.  If the wire is exactly an even multiple of
> 1/2 wavelength long at your frequency, it will have a very high
> impedance.  Just adding or removing a few feet will change this.  Or
> just see if it works on another band.
> 
> Also, you may already know this, but you will possibly have to adjust
> the inductance as well as the capacitors on the tuner.  It should be
> possible to load almost any reasonably sized wire with an ATU; the poor
> ground and low location of the wire may cause it to be a poor radiator,
> or it may give you 'RF in the shack' problems.
> 
> Vic K2VCO
>