02-28-2014, 10:57 AM
Does anyone know why some tubes have a blackish coating inside on the glass? I have seen this on a lot of output tubes, such as the 50L6GT & 6V6G/GT. Some rectifiers also. Is this some type of shielding?
I am also curious about the "getters" and the coating around the getter in the glass. Some are D getters, some are round, some have silver coating, some bronzish color. I know what the getter does, just wonder what it is, etc. I have also seen some output tubes 6BQ5, 6LQ6, ...that look 'burned' on the glass, kind of like an impression of the plate and supports, like there may have been some kind of flash inside at some time, is usually a darkish color. They usually test fine. I havent read anywhere in any of my old books where it explains this. Just curious about this.
I am also curious about the "getters" and the coating around the getter in the glass. Some are D getters, some are round, some have silver coating, some bronzish color. I know what the getter does, just wonder what it is, etc. I have also seen some output tubes 6BQ5, 6LQ6, ...that look 'burned' on the glass, kind of like an impression of the plate and supports, like there may have been some kind of flash inside at some time, is usually a darkish color. They usually test fine. I havent read anywhere in any of my old books where it explains this. Just curious about this.
If I could find the place called "Somewhere", I could find "Anything"
Tim
Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44
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