Lathem DDC4-RS-24 - Manual (Page 9)

LTR-GPS Installation and Setup Guide
After setting the LTR-GPS switches, then mount the active antenna. Locate
the antenna at the highest elevation possible, with a wide view of
unobstructed, open sky. If possible, avoid mounting the antenna on the north
side of a building, which might block exposure to satellites.
Proper locations for antenna mounting:
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