I think this peculiar clock is only ever seen in Starsky’s Ridgeway house in “A Coffin for Starsky”, an episode in which time was of the essence and clock’s had to be properly visible. This clock is not there on Starsky’s bedside table in the previous episode, “Running” (there he seems to have a bulky radio – possibly a clock radio?).
I was informed by Matsir that this clock a Nixie tube clock, and some lucky googling for images of Nixie clocks led me to this page with old electronic clocks, where this exact model is described! It is “Venus”, made by Data Time Inc. in Beaverton/Portland, OR, in the early 1970s. The site says it cost $150 as new – we know from various episodes that Starsky enjoyed expensive watches, so why not clocks, too? (On the other hand, by 1976, this clock would maybe have been a few years old. Let’s say, if Starsky had purchased it in 1976 for $100, it would still equal a $440 purchase today…. Not exactly cheap for a bedside clock!)