Where is the non-nuclear EMP?

Discuss the Traveller RPG and its many settings
Moppy
Lesser Spotted Mongoose
Posts: 619
Joined: Sun Oct 04, 2015 12:42 pm

Where is the non-nuclear EMP?

Postby Moppy » Sun Jun 02, 2019 3:23 pm

I'm having trouble finding one of these things in the Traveller rules. Certainly Mongoose CSC has nothing of the type that destroys instead of jams.

Conceptually one way to make these is to just scale up the generator from a microwave oven. The engineering is of course not that easy. However I am sure the power generation at TL 9+ is up to the task. What's the reason these things don't exist? If they don't work in universe, why does nuclear EMP work?

The largest laser today (at NIF) delivers about 2 megajoules to the target, fills a whole building and took several years to make it work properly. I remember that being in the range of vehiclular cannon or GMPGs (whole burst) from one of MegaTrav or TNE.
Sigtrygg
Greater Spotted Mongoose
Posts: 1263
Joined: Sat Aug 12, 2006 9:23 am

Re: Where is the non-nuclear EMP?

Postby Sigtrygg » Sun Jun 02, 2019 3:35 pm

Look in HG2e for what they laughingly describe as an ion weapon (wonder where they ripped that off). It's affects are almost what you would expect from an emp projector. Ignore the description of anything to do with ions and instead go with it being a focussed emp.
Moppy
Lesser Spotted Mongoose
Posts: 619
Joined: Sun Oct 04, 2015 12:42 pm

Re: Where is the non-nuclear EMP?

Postby Moppy » Sun Jun 02, 2019 3:54 pm

For a weapon system, I'd expect burned circuits and permanent damage, but I suppose it's a game balance decision?

Does that ion cannon exist in personal or vehicle scale?

This leads to another question: If Mongoose nuclear missiles don't do EMP damage to spacecraft, why not? There might not be an atmopshere to carry charge, but on a hit that doesn't englobe the whole ship, there should be a potential difference across the ship itself ... unless I don't understand how radiation works, which isn't impossible.
AndrewW
Cosmic Mongoose
Posts: 4226
Joined: Fri Dec 19, 2008 11:57 pm

Re: Where is the non-nuclear EMP?

Postby AndrewW » Sun Jun 02, 2019 4:03 pm

Moppy wrote:
Sun Jun 02, 2019 3:23 pm

Conceptually one way to make these is to just scale up the generator from a microwave oven. The engineering is of course not that easy. However I am sure the power generation at TL 9+ is up to the task. What's the reason these things don't exist? If they don't work in universe, why does nuclear EMP work?
Just have MacGyver whip one up out of a microwave for you.
AndrewW
Cosmic Mongoose
Posts: 4226
Joined: Fri Dec 19, 2008 11:57 pm

Re: Where is the non-nuclear EMP?

Postby AndrewW » Sun Jun 02, 2019 4:05 pm

Sigtrygg wrote:
Sun Jun 02, 2019 3:35 pm
Look in HG2e for what they laughingly describe as an ion weapon (wonder where they ripped that off).
Yes, there was a desire to support multiple systems hence the ion cannon.
Moppy
Lesser Spotted Mongoose
Posts: 619
Joined: Sun Oct 04, 2015 12:42 pm

Re: Where is the non-nuclear EMP?

Postby Moppy » Sun Jun 02, 2019 4:40 pm

AndrewW wrote:
Sun Jun 02, 2019 4:03 pm
Just have MacGyver whip one up out of a microwave for you.
Hobbyists have done, but not at a useful scale (TL restrictions are so inconvenient).

edit: And also aggro from the police if you did :-)
Gentleman John
Mongoose
Posts: 112
Joined: Thu Dec 14, 2006 9:19 pm

Re: Where is the non-nuclear EMP?

Postby Gentleman John » Mon Jun 03, 2019 3:34 pm

Moppy wrote:
Sun Jun 02, 2019 3:54 pm
This leads to another question: If Mongoose nuclear missiles don't do EMP damage to spacecraft, why not? There might not be an atmopshere to carry charge, but on a hit that doesn't englobe the whole ship, there should be a potential difference across the ship itself ... unless I don't understand how radiation works, which isn't impossible.
EMP only happens if there is a sufficient density of molecules for the Compton Effect to be significant. Then you need a ground plane for the charge to drop to. You tend to get neither of those in free space.

Of course, if you were to build an implosive field generator and mount it on a missile, then you could have all the EMP you want. But the mechanism involved in the generation of the EMP is now completely different.
Moppy
Lesser Spotted Mongoose
Posts: 619
Joined: Sun Oct 04, 2015 12:42 pm

Re: Where is the non-nuclear EMP?

Postby Moppy » Mon Jun 03, 2019 4:12 pm

Gentleman John wrote:
Mon Jun 03, 2019 3:34 pm
EMP only happens if there is a sufficient density of molecules for the Compton Effect to be significant. Then you need a ground plane for the charge to drop to. You tend to get neither of those in free space.

Of course, if you were to build an implosive field generator and mount it on a missile, then you could have all the EMP you want. But the mechanism involved in the generation of the EMP is now completely different.
what is wrong with this below?

the hull itself has the density and if only one half is hit and becomes charged by particle bombardment (radiation is electrons, or helium ion etc, all of which are charged?), you now have a "ground" at the other end of the hull. current flows through the hull to even it out, instant emp.

typed on a phone so no caps.
Gentleman John
Mongoose
Posts: 112
Joined: Thu Dec 14, 2006 9:19 pm

Re: Where is the non-nuclear EMP?

Postby Gentleman John » Tue Jun 04, 2019 7:00 pm

The ship - and the fireball - are essentially free-floating in space. There is no ground plane, merely areas of different electrical potential. Is the ship at a higher or lower potential than the plasma from the explosion (caused by vapourisation of bomb casing, unfissioned nuclear material, filler)? That is not a question because the ship will have an overall neutral charge, and the plasma from the explosion comes from neutrally-charged materials, the plasma will have an overall neutral charge. Even if you apply the Compton Effect to the plasma, there is nowhere for the charge carriers to go to. So, unless you have an extreme polarisation of charge, there will be no real charge differential.

Now - the ship. Yes, the Compton Effect will take place in the hull of the ship. In this case, it is better known as the photoelectric effect. The gamma photons will interact with the hull, liberating electrons. However, because of the density of the hull material, the electrons will recombine with the atoms of the material. Now, if you want to talk about the effects of the gamma photons on charge-sensitive electronics or the effects of neutrons on substrates, you will get an effect that is similar to EMP, but it is not EMP. The charge generated by the photoelectric effect will burn-out the electronics, but the mechanism will be the same as that seen when a cosmic ray strikes an electronic gate of appropriate dimensions. It is not EMP. The neutrons will literally destroy the device substrates, but that is not EMP.

If you were to put a hideous electrical potential onto the ship and remove almost completely all charge carriers of a single specie, then you could generate an EMP in free space. As it is, the optimum airburst for EMP is reckoned to occur at an altitude of 50 miles. There is still atmosphere, a nearby ground plane and the potential for charge to flow. Any higher, and there is insufficient atmosphere. Any lower and you get recombination of the charge carriers, limiting the effects of the EMP.

Hint: there is a reason why gamma-sensitive radiation detectors tend to be made from thin-walled chambers, that are preferably non-conductive. They are then filled with a low-pressure gas and a high electrical potential put across them.

As I said, go for an implosive generator. It's cheaper, a lot less fuss, and the Imperial Navy will not hunt you down for having nuclear weapons.
AnotherDilbert
Cosmic Mongoose
Posts: 3693
Joined: Wed Dec 23, 2015 2:49 pm
Location: Sweden

Re: Where is the non-nuclear EMP?

Postby AnotherDilbert » Wed Jun 05, 2019 9:36 am

Moppy wrote:
Sun Jun 02, 2019 3:23 pm
I'm having trouble finding one of these things in the Traveller rules. Certainly Mongoose CSC has nothing of the type that destroys instead of jams.
Small stuff, but CSC, p119 & 140.
CSC, p119 wrote:This grenade unleashes a burst of electromagnetic radiation that does not harm living tissue but causes unshielded electronics to shut down for 1D minutes. Unshielded electronics of more than two TLs lower than that of the grenade will be permanently fried, while all electronics of more than two TLs higher will be completely immune.
Moppy
Lesser Spotted Mongoose
Posts: 619
Joined: Sun Oct 04, 2015 12:42 pm

Re: Where is the non-nuclear EMP?

Postby Moppy » Wed Jun 05, 2019 10:40 am

Gentleman John wrote:
Tue Jun 04, 2019 7:00 pm
Thank you, this helps.
AnotherDilbert wrote:
Wed Jun 05, 2019 9:36 am
Great, I missed that when I searched the book. I think must have done 'emp' instead of 'electromagnetic'.
Gentleman John
Mongoose
Posts: 112
Joined: Thu Dec 14, 2006 9:19 pm

Re: Where is the non-nuclear EMP?

Postby Gentleman John » Wed Jun 05, 2019 5:20 pm

You're welcome.

Who is online

Users browsing this forum: Bing [Bot], Google [Bot], Sigtrygg and 11 guests