[TenTec] Jupiter Antenna Tuner Question

[Jeff Camp]

I recently acquired a Jupiter in nice condition.  The previous owner 
listed the radio as not having an automatic tuner, but when I go into 
the menu I can see an option to turn it on and off.  When the option is 
set to off and I press the tune button, the Jupiter transmits as 
expected until I press the button again.  When I set the option to on 
and press the tune button it acts like it's trying to find a match 
(transmits for a second or two) and then stops on its own.  I can't find 
anything about this in the manual but does this mean the radio actually 
has the automatic tuner?  I use an external tuner, but it would be nice 
to know this in case I ever decide to sell the radio (fat chance).

Thanks,
Jeff
N0WJP