The Lionel Multi-control 1033 is a 90 watt transformer produced from 1948 to 1956. They are reasonably durable and were popular in their day, which means there are still a lot of them floating around so they tend to be inexpensive. I paid $70 for one about 15 years ago but the price has come way down; today you can get a serviced 1033Â for about half that, and an as-is one for $20-$25.
Even someone who has a larger transformer or multiple larger transformers for the layout might be interested in a 1033 for the test bench, as it has all of the functionality someone would need for testing locomotives and whistling tenders.
David Farquhar is a computer security professional, entrepreneur, and author. He started his career as a part-time computer technician in 1994, worked his way up to system administrator by 1997, and has specialized in vulnerability management since 2013. He invests in real estate on the side and his hobbies include O gauge trains, baseball cards, and retro computers and video games. A University of Missouri graduate, he holds CISSP and Security+ certifications. He lives in St. Louis with his family.