Motorola had an older factory on 4545 Augusta Blvd. in Chicago, I assume they closed this plant when they moved to Franklin Park. I was there about a year ago and it was now a seating company. It's nice to see that it is still something related to manufacturing instead of lofts.
This was where my Motorola UHF converter was made. I belive this plant was used until the mid 1950s?
If you are intersted, there is a picture of the factory in its present state on the second page of this thread:
http://www.audiokarma.org/forums/showthread.php?t=82229