[Elecraft] KAT3 ATU and SPE Expert 1K-FA Amplifier

[Chris Page]

My K3 has the KAT3 ATU fitted and I therefore have the options of 
selecting ANT 1 and ANT 2.  I use the K3 with the SPE Expert 1K-FA 
amplifier.

After looking at the diagram showing the switching of the KAT3 in the 
K3 Owner's manual, am I right in thinking that when transmitting (I 
am a CW operator), there should not be any RF on the antenna not 
selected?

I use ANT 1 for all my HF antennas, including 6m, and ANT 2 for a 
resonant inverted vee for 60m that I put up yesterday.

The reason I ask the question above is that when I select ANT 2 (for 
60m) and transmit, the 1K-FA immediately goes into STANDBY mode 
because of a high SWR.  

I am wondering if my KAT3 ATU is working properly?  With the KAT3 in 
BYPASS mode (which is how I have been using it for all my HF 
antennas), the K3 SWR meter gives an SWR of 1:1 on 60m, which it 
should do as the antenna is resonant.

When I switch the ATU to the AUTO position on 60m with the same 
antenna and then tap the ATU TUNE button, the K3 makes a similar 
noise to the K2 ATU I have, but does not display any readings.  When 
I then transmit, the SWR meter shows maximum SWR and about 40 watts 
output with the K3 power contrtol set to 100 watts. 

I have tested the KAT3 relays using the L1-L8 and C1-C8 and Ct 
settings in the KAT3 CONFIG menu and they appear to be working ok.

This is the first time I have needed to use the KAT3 ATU or the ANT 
1/ANT 2 facility since I got the K3.

I would appreciate any advice or suggestions, please.

Thanks and 73 de Chris, G4BUE