so in 1929 a PSB of sorts was already in use... That's a lot earlier than 1936 (sorry Yorkshire!)The lever frame is a Westinghouse Style 'L' Power Frame and was the first all electrically locked frame of its type in the UK,
It's strange, Wikipedia says it was a Westinghouse installation, but I can't find any mention of Hull at all on this websiteDon't know much else, apart from the fact it replaced a 1904 electric locking system
Lime Street signal box is the last miniature lever frame on the national network and dates from the 1940s. In terms of the more contemporary PSBs that were installed until the 1990s I would imagine Edge Hill is a contender from the 1950s.
Because Hull was 'refurbished' or should I say 'stripped and halved' in 1984.
I thought Maidstone East still restained it's immature level frame for the station area along with more modern panels for the fringes to Victoria ASC and Ashford IECC.