[Elecraft] Muting one K3 while other is transmitting

[Fred Jensen]

To the original post: "muting" the second K3 [i.e. silencing it] does 
nothing to "protect" it from excessive RF input ... and possibly I 
misunderstand the post too.

This was the subject of a thread not long ago on the list.  If the two 
antennas are in each others' near fields, the antennas are a coupled 
system and the power delivered to the receiver from the other antenna 
can be [and likely will be] enough to damage the receiver.  I've seen it 
happen to a K3.

Unfortunately, the end of the near field and the beginning of the far 
field is undefined at HF, near just fades into far.  It's a function of 
wavelength and size of the antenna among many other factors.  The near 
field of a Voice of America sterba curtain on 20 MHz is likely much 
larger than that of a ham dipole on 80 meters.

I would advise great care and some measurement unless you can assure 
that the two antennas are definitely not parasitically coupled.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2014 Cal QSO Party 4-5 Oct 2014
- www.cqp.org

On 3/8/2014 10:25 AM, Jim Brown wrote:

> That depends on the spacing and directivity of the antennas to which the
> two transceivers are connected.