This page is part of the Tools section of the Wiki.
TTL Testers are tools to check 7400 Series TTL chips popular in pre-CPU video games of the 1970s. Chips are typically tested out-of-circuit. Testing TTL chips in-circuit is usually done with inexpensive logic probes or more expensive TTL Logic Comparators.
TTL testers can check most, but not all 7400 series chips, the exceptions are a few exotic chips that don't respond t0o stimulus in a typical manner.
Historically restorers have purchased new or used TTL testers online or on eBay, typically for $100-200. A particularly popular model is the 'Portable Digital IC Tester' model Express HT-28 by Data Genie. The identical unit is sold under a variety of other names including the LBT-10 by LBT.
In recent years low priced TTL testers have become available, and by 2013 they have been found online very inexpensively. Often these low priced units consist of a socket, circuit board, and small display without even the luxury of an enclosure case.