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North Korean Vacuum tubes

Thank you for your input Jan, nicely put. Some more info found in the attachments. As I said, I am not a connoisseur but I do have a fairly large quantity of tubes (about 30k) and a successful eBay store to flaunt them on, it is just with these tubes, I have no idea how to handle them.
 

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You sure they were made in 1980??


Top row look like 1940,s bakelite based IO-8 .


Row of steel cased ones look like military versions --if that's NK in the 1980,s how the heck have they reached to a industrial stage of nuclear bombs and missiles ?



Looks to me as if they bought old tube/valve making machinery from maybe the USSR -very old school !
 
I am very familiar with this shape and type of color in old UK/USA etc military communication gear of WW2 .


The dark coating conforms to v4lve post of being 6V6GT as well as 6SN7 of typical 40,s style .


In the UK it was standard practice to make radio audio tubes/valves of earlier and in the 40,s in IO-8 based with a dark coating on the glass ,they certainly look like 6V6GT --if so they are worth buying .
 
"Clones " ?--- they look the most original looking clones I have seen for a long time .


If you mean manufactured by equipment bought by NK from --possibly the USSR well yes .


Clones to me are mostly inferior to the original manufacturer but if you use a countries equipment that produced quality tubes/valves then that would not be inferior .
 
If you mean manufactured by equipment bought by NK from --possibly the USSR well yes .

Clones to me are mostly inferior to the original manufacturer but if you use a countries equipment that produced quality tubes/valves then that would not be inferior .
Equipment isn't everything.
There are lots of Chinese tube types that are direct Soviet clones and are (still) made with the ex-Soviet equpment. Not all of them are good.
 
if that's NK in the 1980,s how the heck have they reached to a industrial stage of nuclear bombs and missiles ?
Well, USA had Nukes and Missiles, controlled by tubes, until the 80´s.
I often mention the last US based Tube Factory making special ones for USAF anti missile pods during first Iraq War , 1990/91 .

This is part of the Guidance Computer from a Hawk Surface to Air Missile, built by Raytheon.

Notice the subminiature pencil tubes inside aluminum shields:
xd144.80p-03-13.jpg


xd144.80p-03-18.jpg


Turrets, eyelets, PTP wiring, carbon composition resistors, paper in oil caps, tightly wrapped wire bundles, mucho Mojo there.

A plane hit by that missile will be as dead as one driven by the latest microprocessors:

xd144.80p-03-02.jpg


Minuteman missiles couldn´t rely on SS or Flash memory, so they carried target and guidance information on a **hard disk*
 
Well, USA had Nukes and Missiles, controlled by tubes, until the 80´s.
I often mention the last US based Tube Factory making special ones for USAF anti missile pods during first Iraq War , 1990/91 .

This is part of the Guidance Computer from a Hawk Surface to Air Missile, built by Raytheon.

Notice the subminiature pencil tubes inside aluminum shields:




Turrets, eyelets, PTP wiring, carbon composition resistors, paper in oil caps, tightly wrapped wire bundles, mucho Mojo there.

A plane hit by that missile will be as dead as one driven by the latest microprocessors:



Minuteman missiles couldn´t rely on SS or Flash memory, so they carried target and guidance information on a **hard disk*
lots of german made capacitors though...