brown-black getter flashing does not mean ‘Used’!

Discolored getter flashing (brown or black marks) does not mean that a tube was used. This fiction is believed by both uninformed buyers and seasoned tube jockeys. This myth seems credible because some new tubes have perfect shiny mirror getter flashing; therefore the assumption is that brown or black stains in the getter flashing must indicate a used tube. The myth says that the more brown/black discoloration, the “more used” the tube is. Wrong.

Excerpt from Electronics Magazine

Excerpt from Electronics Magazine

The purpose of the tube getter and flashing is to remove gas inside the tube envelope during manufacture. This discoloration myth can be quickly debunked by reading the article in Electronics magazine, October 1950, entitled “Getter Materials For Electron Tubes”. The article explains that if the getter is vaporized very slowly during the manufacturing process, “the first barium atoms evaporated will absorb the gas present so that the remaining getter is deposited in a very high vacuum, exhibiting a shiny mirror.” If the getter was flashed very rapidly during manufacturing, then “the getter mirror will be discolored due to the dispersion of the barium.” The article then explains that the discoloration “does not mean that the getter is contaminated, but merely that the deposit is finely divided and therefore absorbs light.”

Several photos of NOS tubes below demonstrate this myth.  Likewise, I provide photos to demonstrate how the flashing looks when a tube is actually used. Let us proceed…


NOS NEW Tucker Torpedo Auto Radio

Occasionally I plan to write about a few of my favorite items from my personal collection. Here is an NOS NIB NEW* genuine Tucker Corporation auto radio, built for the 1948 Tucker Torpedo car.

Tucker Corporation was the company founded by Preston Tucker to sell his revolutionary 1948 Tucker Sedan, known by most people as the Tucker Torpedo. This is the genuine Tucker factory radio for the Torpedo, NOS NIB NEW.

NOS NIB NEW Tucker Torpedo Radio

This radio was found from a very elderly man who had “put a down payment on the car” and someone told him that he “had to buy the radio right now” (even though the Tucker Torpedo had not been built yet!)

Obviously, the Tucker Torpedo was never built, so the old fellow was left with a new car radio that he could not use. So, it sat on a garage shelf for more than 50 years until I purchased it from him.

Here are some interesting facts about the radio….


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