I just saw this on my Star Trek.com feed on Facebook, confirmed by the New York Times, Fox News and others: Tim O'Connor whom I grew up watching as 'Dr Huer' on season one of 'Buck Rogers in the 25th Century' has died aged ninety from cancer. Rest in Peace Mr. Connor. I also remember is guest appearances in 'The Six-Million Dollar Man' and 'Star Trek: The Next Generation'. According to the article he really was from Chicago which makes his line to Buck in the pilot of BR25C 'There's nothing like Chicago left on Earth.' all the more poignant. 
https://www.nytimes.com/2018/04/13/...plex-resident-of-peyton-place-dies-at-90.html

https://www.nytimes.com/2018/04/13/...plex-resident-of-peyton-place-dies-at-90.html