[TowerTalk] Reflector in the back of shunt tower for 160m

[Jim Brown]

All great advice. And even 1.5 dB can be the difference.

73, Jim K9YC

On 1/27/2022 9:19 AM, VE6WZ_Steve wrote:
> Be aware that the gain and F/B of the array is very sensitive to parasitic loss.
> Ground loss will quickly diminish the current in the parasitic and the gain will crash.
> It’s easy to model this.  Just include a series resistance in the parasitic element and watch the gain and F/B drop.
> 
> Field measuring the gain with on air tests can be difficult.  With only 3 or 4 dB forward gain compared to the single vertical, it can be very hard to measure.  Even using RBN reports, QSB can easily mask this small change.
> However, 3 dB is, well…..3dB and it's like doubling your TX power.  For the really weak QSOs, when your signal is just bubbling around the noise, that 3dB can make the QSO.
> 
> I recommend you read about my tuning method. It is not a trivial process to tune the parasitic to match the model.