Anyone know how to create an electronic KN2 tube ?

[Vaporware]

Hi Steve,
Schematic sent. You should be getting it shortly.

I think you are correct about the bait idea. Solid state solutions have been around for 15 plus years. Of course the Kolrad K2 is so old (1970's) a solid state solution was not available at the time or was too unreliable.
I did send off an email to the sales people of one of the links you sent. Have not heard back yet.

Tom

[LesioQ]

I think this is the simplest=most available (as opposed to avalanche transistors) krytron replacement in Pockels cell driver application.
Piotr.K

[heroic]

Hi Steve,
Schematic sent. You should be getting it shortly.

I think you are correct about the bait idea. Solid state solutions have been around for 15 plus years.

Solid state solutions are also covered under the "dual use technologies" rule, and if you start selling fast switching modules that are fast and high current enough you will get a knock on the door. No, really- I worked for a company where it happened. Funny story, we were selling them to pulse welding machine companies who couldn't use trigatrons any more because of the mercury in them!

The reason the parts were banned has nothing to do with the radioactive nickel in them. It's all about the fact that they can be used to trigger exploding bridgewire detonators with great precision and repeatability.

Last time I had to fix a broken krytron I did it by scraping (carefully, wearing vinyl nitride gloves and a dust mask) a little radium paint off an old radio, putting a drop of superglue on the krytron's envelope and using tweezers to stick the chip of paint to the drop of glue. Then I threw out the gloves, the mask, the tweezers and the radio... the gamma rays from the radium paint were enough to restore the krytron to operation.

[Vaporware]

I am not worried about a 'knock on the door'. We have a legitimate and provable need. I think a couple semiconductors is not enough to actually cause concern but I could see the problem if I was manufacturing an item like a welder. I am just repairing an item. I would prefer to just replace the item with a solid state solution rather than scraping off old radium paint I do understand it it is not the radioactive nickel but the purpose of the device which is the concern. Of course many things can be misused. I just found it interesting that the KN2 was detectable at a distance with only a small number of devices. I also would prefer to eliminate any radioactive parts in the workplace if possible so that is another reason to replace it with something more modern.

So what happened in your 'knock on the door' event. Did they just say stop selling or after it was all traced out did they just go away ?

Tom

[heroic]

They basically forced us to either get certified to handle dual-use devices and material (which, as a small electronics manufacturer, was basically impossible- security requirements alone were prohibitive) or to stop making it.

We stopped making it- changed the design to add more jitter and slower commutation, which made it fall just outside the bounds of the IAEA definition, which made the government happy.

[Vaporware]

They basically forced us to either get certified to handle dual-use devices and material (which, as a small electronics manufacturer, was basically impossible- security requirements alone were prohibitive) or to stop making it.

We stopped making it- changed the design to add more jitter and slower commutation, which made it fall just outside the bounds of the IAEA definition, which made the government happy.

That is basically what happened to Perkin Elmer. The certification and dealing with a radioactive part by the government were so costly it was just cheaper to destroy the production line and get out of that business. From my talking with the P&E guy it was interesting to note the government was the largest buyer of the part.. Ironic.. The government kill off their needed supplier of the part. Typical..

[heroic]

That is basically what happened to Perkin Elmer. The certification and dealing with a radioactive part by the government were so costly it was just cheaper to destroy the production line and get out of that business.

The problem is not what goes into them (there are *many* electronic devices that contain radioactive material, and they are not a problem) but what they can be used for (building nuclear weapons and advanced radars).

[Vaporware]

The problem is not what goes into them (there are *many* electronic devices that contain radioactive material, and they are not a problem) but what they can be used for (building nuclear weapons and advanced radars).

With P&E selling the majority units to governments which they had done for numerous years I am pretty sure P&E and the government knew how they were being used. I got the impression from the P&E rep it was the massive change in the certification to handle radioactive material and the additional cost that made the bulk of the decision to kill the production. At some point jumping through hoops gets to be too much

Tom

[heroic]

With P&E selling the majority units to governments which they had done for numerous years I am pretty sure P&E and the government knew how they were being used. I got the impression from the P&E rep it was the massive change in the certification to handle radioactive material and the additional cost that made the bulk of the decision to kill the production. At some point jumping through hoops gets to be too much

Tom

Unfortunately the export control dudes don't care how they *are* being used, they only care how they *could* be used... the paperwork and physical security required are a huge problem, and getting background checks and clearances for everyone with physical access to the finished components is just a nightmare.

I do know that krytrons *are* still used- they combine being very fast and repeatable with being resistant to overvoltage, EMP and other such nasties- but you're going to have a heck of a time finding one.

As for building a solid-state replacement, do you have specs for the KN2? if so, I'm sure we can help you cook something up. Hopefully without incurring the wrath of any government agencies

[mixedgas]

Heroic wrote:
I do know that krytrons *are* still used- they combine being very fast and repeatable with being resistant to overvoltage, EMP and other such nasties- but you're going to have a heck of a time finding one.
end quote

Uncle sam and Uncle Ivan both now hire expensive contractors to make reproduction tubes. There are 3-4 companies that do no nothing but run old vacuum tube lines as one offs, very quietly,and very expensively, for Uncle. Some of the big projects, like linacs, have went to refurbing their own big RF tubes.

Uncle went to laser/fiber triggering for the big boom stuff. The government lab that developed it was far less less then quiet when it came around to funding time and when they were about to get axed. Its down state from here. They never "said" it was for big booms, but its implied.


I sent a link for the spec sheet to heroic.