(Login Nafana) Forum Owner Posted Apr 11, 2010 11:01 PM
I suspect the "burn marks" you saw was where the "getter" was flashed during manufacturing process to remove residual oxygen. Most tubes had that to varying degrees. Yes you could usually fix sets by replacing tubes (and often cause good tubes to go bad from the jostling). My first job- at 15- was in a TV repair shop. We always resented the "tube-pullers". They only brought us only the "dogs"- set with bad resistors, capacitors, diodes, etc that were time consuming to track down and replace.
In those days there was a TV repair shop on practically every corner- now there are hardly any- first because new sets don't break down as much- and when they do they are so difficult and expensive to repair that it's usually makes more sense to get a new one. This is true of almost all consumer electronics now- it's not designed to be repaired. You take your cell phone in for repair and if it's anything more than a battery the guy will just toss it a bin and give you another. Even at the station where stuff is too expensive to toss- our once busy repair bench sits idle now because today's equipment requires so much specialized tools and parts to fix that only the factory can do it. So signal paths are designed in parallel so equipment that is off for repair can be bypassed.
But as much as I'm nostalgic about the "old days" I must admit you get a lot better TV today for a lot less money. But the same automated manufacturing processes that makes them cheap to manufacture make them almost impossible to repair when they do break.
By the way I still have a TV that has tubes in it! I bought in 1971! It's in a guest bedroom and is never used now but it still works! I've often wondered if I might win some contest for having the oldest still functional TV around!