/ GT tubes - Printable Version

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/ GT tubes - bill T - 03-13-2007

Hi all, Just for those interested the original tube in my 41-95 were all replaced with much cheaper GT tubes and they worked fine.
I have now put back the good originals .
The only different I see is the style of the tube bulb itself .They all shared the same data sheets so electrically they are the same .The GT's are much shorter .And way less expensive. All are glass. The original non gt type did not have shoulder but did have plastic bases. We have all used sub's in one place or another .This was a total swap and it seemed to work fine.Becuase of the price differences I though I would pass it along.
I like to save my originals and run subs anyway.Found a good post below on the subject . This is good info so I copied it here.>>>

"designation GT stood for Glass Tubular, meaning that the tube was cylindrical and made of glass, as opposed to the earlier "ST" shape, which had shoulders. The ST shape replaced the "globe" shaped tubes of the 1920s. GTs and metal tubes were contemporary, and were often at odds with each other. GTs sometimes will not satisfactorily replace metals, and vice versa. In metals, pin 1 is always grounded to the chassis, and in some radios meant for GTs, and GTs alone, they used pin 1 for a handy tie point for components, and it might be raised to B+ levels of voltage, so that if you plug a metal tube in that socket, the tube body will be at high voltage."
I hope the person who wrote this does not mind I copied it here . It was worth passing along.

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