Anyone ever have, use or hear this tube?

Yeah, anything labeled for lab equipment and such used the tested cream of the crop. And you pay for those little letters and stickers!

@audioman58 ,

You think you’re the only one with tube knowledge and experience? I’m well aware of where nos tubes come from. They are what I research and buy exclusively. I’m also aware of the common ones, the rare ones and the ones in between. I’m aware of the applicable prices. I’m also aware of reputable companies that sell them, tested, matched, and readings confirmed with a print out. Although I appreciate you taking time to post, your blunt, rigid statements leave a bit to be desired.

@wharfy ...reminiscent of ee cummings, actually......waiting on taking a 'breath', so to....type... ;)

Not here to judge....just edu-lurking anyway....

@asvjerry 

LOL!!!! A terrific A'Gon post, with my morning coffee. 

@wharfy, i dont know what the real price of these tubes is, but tubedfepot.com typically sells at 2x-4x the legit retail price and even buy from retailers, just like any end-user, and jack up the price. their testing is minimal. theyre great for new production, especially for guitar amps, but for old stock their preice gouging and minmal expertise is a last resort. they also mis-identify OLD stock tubes, making basic mistakes like asserting that philips-labelled EI yugoslavia tubes, of which they sent me several pics clearly showing EI yugo codes,  are really philips. https://www.tubedepot.com/products/7dj8-pcc88

after i informed them, they made no correction. 

for old stock tubes, the big three are brent jessee, jim mcshane (mostly retired), and andy/vintage tube services. andy takes a very, very long time, but hes quite strict. 

there are some excellent second-tier dealers as well, like tctubes. 

@cey 

Good info. I did not know that. TY!

Anyone remember when "Tubes" was a very, very active category on A'Gon? Pages of NOS offerings. Today, I saw 29 listed.

David