[Elecraft] Possible K3 Antenna Input Leakage

[Wayne Burdick]

Hi Ron,

Isolation between antenna ports on the KAT3 is typically 30-40 dB when terminated in an antenna or dummy load, varying somewhat with band. Isolation can appear to be worse when you switch to an antenna jack that is unterminated, because the impedance is very high, making it more susceptible to leakage between PC board traces, relays, etc. But even 20 dB isolation should suffice for most applications. 

73
Wayne
N6KR


On Jun 24, 2014, at 8:33 AM, Ron Schwartz <rs500cat at icloud.com> wrote:

> I recently completed a K3/100 kit (great experience)!  I have noticed a sizeable leakage between the ANT1 and ANT2 inputs.  On 20M, signals appear on ANT2 when there is no antenna connected, about 4 S-units below the level on ANT1 (where the antenna is connected).  On 40M the difference is slightly greater.  Just wondering if this is normal?  Perhaps I did something wrong when building the kit.  The radio does have the KXV3A RX antenna interface option installed, but not the sub receiver.
> 
> Thanks, Ron
> K2RAS