What Is Wrong With This CRT?
 

It's what they all call a cataract. It's a mold contamination between the outer glass and the CRT glass.
Do a search on the different methods of removing the glass.
I would first determine if the CRT is still good. If it's the original, probably not.
If it's been replaced, possibly so. :scratch2:

The CRT is not affected at all and may be good as new, assuming it has decent emissions. The adhesive that bonds the integral safety glass to the face of the tube has deteriorated.

It is no small feat (and can be highly dangerous) to replace the adhesive, but it can be done.

ETA: ninja'd by the faster typist dieseljeep

...

you're lucky, I have had several that were under vacuum and could not be rejuv, had one that had a single open filament (blue gun).

My typing skills are still hunt&peck.
I went to school the be an electrician. The school offered a typing course, but the only students, that took it, were the ones that were going to college. I'm out of high school, for like fifty-one years. :thmbsp:

Hey, I saw that set on eBay. Seller wants 2 1/2 bills for it. Middletown PA, local pick-up only.

http://www.ebay.com/itm/Vtg-RCA-VICT...e/360892284482

If you're set on getting a round tube set, my choice, hands down, is the RCA CTC16 series. The CTC16X, being the last of the high performance roundies.
The last of the Zenith roundies, the L,M and N models aren't bad either.
The set shown is the last of the RCA round tube sets, an entry level model, they designed to use up, left over parts. Nowhere worth the asking price. :thumbsdn:

Isn't that a set that is/was on eBay or Craigslist?

See the previous post 3 before yours.

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At least there is the option to "make an offer".

They're really optimistic about what they'll get for that CTC-20, aren't they?