Funny ad for radiotubes...

[B@rt]

I wonder if the seller got his asking price.... :thinking: :tinfoil:

 

[Beamhead]

Those are the new "supply your own vacuum" or the we sell, you suck(er) models.:devil:

 

[chmsam]

"My brain hurts..."

 

[Zeruel]

Take note he said he carefully removed the glass..... maybe the vacuum is still in there afterall?

 

[chmsam]

Ow, ow, ow.

I just hope to heaven that I am not related to that guy. Knowing my luck I probably am.

 

[carrot]

LOL

I like the carefully worded "may still work"

 

[Sgt. LED]

WoW, what a deal!
Submit that for the best of Crag's list right now, he actually took the time to open them and get all that nasty silver stuff off the inside of the glass. Very thoughtful of him. If only I could find new glass................

 

[Radio]

Thanks B@rt! Thats the funniest thing I've seen in a long time, :thumbsup:

 

[smflorkey]

Thanks B@rt! Thats the funniest thing I've seen in a long time, :thumbsup:

Funniest or saddest, I can't decide which. Wow!

 

[nitesky]

Obviously the glass is just superfluous packaging.:sigh:

Old joke...

Two men pull up to one of their houses in a new car with wood panels (very old joke). They immediately set upon the car with tools and rip off all the paneling.

One turns to the other and says, "It looked better in the crate."

 

[FredericoFreire]

Good one Bart! Hard to belive this could happen.

 

[jhanko]

That's hilarious! I just reread the ad and noticed he's asking $50 EACH. What a jerk. Someone close should contact him and request to buy all eight. Tell him you'll come over to pick them up and never show. At least you'll get the satisfaction of knowing he's sitting at home for nothing, waiting for a bigger fool than himself...

 

[Steve K]

I love learning new things! Now I know that it's the glass that makes vacuum tubes work, the same way that the "magic smoke" is what makes semiconductors work.

As a person who has a very basic knowledge of tubes, can someone tell me what is the function of the metallic coating on the inside of the vacuum tube glass? Is it there to act as a shield of some sort? Or is it just the metal that boils off of the heater filament, not unlike the coating that can develop inside an incandescent bulb?

....and how did this guy get the glass off?? This had to be a case where he had a busted tube, and decided to try to sell it anyway, right??

regards,
Steve K.

 

[nitesky]

The seller either did not know, and in innocent ignorance removed the glass, or had some broken tubes and cleaned them a bit to sell. Not sure which I prefer. There could be other possibilities I suppose.

 

[Black Rose]

In the immortal words of Bugs Bunny....What a Maroon.

 

[chmsam]

Let's see if I remember this correctly. The silver coating both dissipates heat and absorbs gases. If the silver on the glass coating is white that means that the tube has a vacuum leak (pretty easy to diagnose this one, huh?) and should be discarded (whoa, like that's a bummer dude). The tube is sort of like a light bulb. It works in a vacuum and the filament in the center is called the cathode. That emits electrons to the plate (anode) and the simplest tubes therefor function as a diode.

By the way, those GE tubes as new old stock (unused but old) go for $75 or more each. That means he could have had $600 or more in his pocket.

Gee, I guess the man in the yellow hat wasn't there to save Curious George this time.

 

[Beamhead]

This will date me but I remember de-glassing tubes as a kid using them for grenades when playing army/soldier.

 

[UncleFester]

I THINK the silver on the inside of the envelope is boiled off metal from what's called the "getter". The getter is a wire loop that forms a closed circuit. After the tube is sealed and vacuumized, a large current is induced magnetically induced into the getter making it hot. The purpose is to consume any remaining air components inside the envelope. I COULD be wrong.

 

[chmsam]

I'm pretty sure that is the case but I think that some tubes were sold with the silver (well, it might not be silver actually) coating to also do that. I could never see another explanation for it on new tubes mostly because it was always too uniform to seem like it was just from testing or otherwise but I do not know for certain. It's not only for incomplete vacuums but also for controlling "off gassing" of materials inside the tube.

Of course when you take the glass off of the tube all bets are off.

 

[PhotonWrangler]

Oh my god!

Yeah, who needs that nasty old vacuum anyway. And I'm sure the sound will be less muffled without the glass in the way!

Thanks for a good laugh, Bart!