Whoops, meant to add a photo of the machine from the linked Reddit thread. By the time I realized it, I couldn't edit my comment anymore.
If this is a closer match to what you remember, it's likely that AlZilla was correct in suggesting it's a Japanese ZigZag machine. From the reddit comments on that thread:
It's a generic Japanese zigzag (relatively new; probably from the 70s or 80s). Atlas is not a manufacturer; it's a badge name.
...
machines sold under this badge were made by Brother. This model is almost identical to the
Brother XL703.
(Source Link:
https://www.reddit.com/r/sewing/comm..._this_machine/)