[Elecraft] K3 power consumption

[aa1o]

Hi Wayne,
I would like to use my K3 for Field Day again this year. I have installed the sub receiver and am concerned about my power budget. I use a 15 watt solar panel to charge a battery and find that the K3 is now drawing over an amp on receive. Is there any simple way to disable or turn off the sub receiver? I am only going to use CW and 5watts output. 
73, Bill AA1O
K3 287
K2 1740