Yes, some components only work on specific types of units.
To make a non-endless supply base, you need to make it a ship. Simply set the engines allowed to 0, and also copy the -50% maintance cost modifer from the base entries. Or change the default entries to "ship" from "base"
Phoenix-D
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Phoenix-D
I am not senile. I just talk to myself because the rest of you don't provide adequate conversation.
-Digger