HP 5245L Repair-a-thon - Part 1: The King of 1960s Frequency Meters

We start repairing our very broken HP 5245L. It is arguably the king of the Nixie frequency meters of the 1960s. Equipped with the right plug in, it could count up to 18 GHz. Many of them were used in the Apollo communication ground stations. But this digital instrument does not use a single IC: it’s all made with individual transistors inside! It feels like repairing a giant IC, but with access to every transistor. We’re sure not complaining about it. Stuff that supports the channel: - Amazon links for the tools I use in the lab (supports the channel if you buy from there) - Channel merch on Teespring: - Support us on Patreon: Our lovely sponsors - PCBWay: fast turn PCBs, - Electro-Rent: - Keysight: test instruments: - Samtec: connectors: - R&D Microwaves: Get more technical info on the companion site: Contact info: