I just purchased a boat with a Sub-Troll 900, that is probably from 1990s. Hoping someone could help me with a couple questions: 1) Does anyone have a manual for the Sub-Troll 900 that they could share. Checked out the "Zip File" in another thread, however it is no longer active. 2) Also wondering if it is normal to see no temperature reading when the probe is out of the water. When I power up the unit in my garage, all I see is the decimal point on the display. I assumed it would read/display the ambient air temp??? Thanks for any help!