Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
green gun dead, or dried out electrolytics in green amplifier. dried out electrolytics are more common, but CRT's aren't made to last either. the small circuit board on the back of the CRT is where you'll find the electrolytics. common values are 1uf/50V, 10uf/50V. there may be others there with voltage ratings as high as 450V, depending on the model of TV. if you don't have a way of measuring capacitor ESR, assume all of them are bad (or will be soon). carefully inspect the board, and write down the value and voltage of every capacitor on the CRT board, and if there's printing on the board, where each cap goes (C101, C201, etc...) replace them one at a time, don't try to strip all of them off the board at once and repopulate the board, it WILL get confusing that way. pay attention to where the minus strip on each one is, because if you put one in backwards, it WILL explode when you apply power to it.
also check the solder connections on the CRT socket. the heating and cooling a tube goes through can break the solder connections on the socket, and those connections will need to be resoldered. check the solder connections of all of the transistors on the board as well, as they also have a tendency to break.
if after this work is done, you still have no green, it is possible the picture tube is bad. picture tubes are more expensive than a new TV, and only an experienced technician should replace one, as there are safety hazards and alignment procedures involved that just plain are not taught anymore since the flat panel has taken over the market...