[zer010gic]

I just received a set of Tung Sols for my WA2, the box they came in was pretty beat up by USPS. While I was removing them from the packaging I noticed a slight rattle. After examining them I found at the bottom of the tubes inside the glass dome where the wires all come in there is quite a bit of free ceramic pieces in there. Their not in the main part of the tube just the dome at the base of the tube. Is this normal, could this indicate the tube is now broken?

 

[Rob N]

Possibly not broken but the only way to be sure is to test them first.

You sometimes get pieces of the glass stem broken and loose in some types of tube,Ive seen it a few times in 5998 tubes

Loose metal pieces are more of a problem because they may cause a short

 

[zer010gic]

This is brown ceramic not metal.

 

[Uncle Erik]

As long as the envelope isn't damaged the vacuum should be intact and the tube should function. What you have to watch out for are broken pins and anything metal in there that could cause a short. If the envelope isn't damaged, the pins are OK, and it's just a little loose, the tube should work. If being loose bothers you, you could always glue it together with a high-temperature epoxy. But I've used slightly loose tubes in a bunch of radios and have never had a problem with them.

 

[xenithon]

I have this rattle with my 5998's too (and a pair of 6AS7G's). They test and work fine though; as per the tube FAQ, a rattle may form due to some dislodged glue (i.e., ceramic-like material), and is harmless. Often happens during the assembly process I believe.

 

[Gvvt]

There must be something about 5998s and related tubes. I had this on a couple of 2399s and 6AS7s. Only in one case was the tube itself dead; the others are all fine.

Whenever it's loose enough to move up out of the base, it's small shards of glass. Some unusual stress in the sealing process?

 

[sacd lover]

Quote:

Originally Posted by Gvvt /img/forum/go_quote.gif There must be something about 5998s and related tubes. I had this on a couple of 2399s and 6AS7s. Only in one case was the tube itself dead; the others are all fine. Whenever it's loose enough to move up out of the base, it's small shards of glass. Some unusual stress in the sealing process?

Yes, but it could also be the tubes just have been banged around over the years. The physically bigger tubes seem to have this problem more often.