[Elecraft] KAT500: Fails to tune, and shows 3:1 on good antenna on 18 MHz.

[Dave Cole]

Hello,
My KAT500 which worked yesterday, now shows a 3:1 on 18 MHz., only. 
Antenna is a single feedline to a 6BTV, and an analyzer says all is good 
at low power.  At 100 watts, all seems good.

All other bands seem OK at high power.

Question:  When in bypass, is the entire tuner bypassed?
Question:  When turned off is the tuner bypassed?  Which antenna is default?
-- 
73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources