Topband: Usable size of Flag antenna and FSM

[Eric NO3M]

Anti-phased double loops are also a good way to approach an RDF of 10dB 
on 2200m (137kHz).  1/2lambda is nearly 3600ft.... so broadside arrays 
and beverages are usually a non-starter... close spaced end-fire 
vertical arrays get very touchy (amplitude/phase).  A DHDL style system 
spanning about 350ft works well here (quiet rural QTH):

http://no3m.net/2020/09/2200m-double-loop-receive-antenna/

The one I use is aimed west and hears VK4YB (and recently VK2AN) on 
2200m most mornings starting a couple of hours prior to sunrise (and at 
times has gone an hour or more past sunrise).

- Eric NO3M


On 2/26/21 12:57 PM, n4is at comcast.net wrote:
> I would like to share some of my experience with small flags'.
>
>   
>
> The directivity is the same for a large chance in frequency but the gain increase with size.
>   

> So a small loop is not thermal noise limited on 160m, and works very well on
>
> 80, 60 40 and 30m.