[Heathkit] GD3511

[WB6BLV (DM06)]

I just found in some stored stuff an unopened Heathkit box labeled
"GD3511".   A Google hit says it is a lighting controller, but I see there
are several lighting controllers made by Heathkit.  Since the original
Heathkit box is unopened, I dont want to try to peek inside at the manua..
Does anybody on the list know exactly what this thing does?

thanks

John
WB6BLV at inreach.com