[amsat-bb] Re: Safekeep Sat Radios

[Bruce Bostwick]

As I understand it, any equipment you want to survive an EMP had  
better be inside a Faraday cage that's actually a solid electrically  
conducting case with no gaps.  The ideal would be a packing crate  
sheathed in copper and soldered shut, not sure if you'd have to go all  
the way to that extreme or if a tight fitting copper lid would be OK  
(I'm sure there's been military research done on exactly how tight the  
seal would need to be).  I'm pretty sure that lead-acid wet plate  
batteries would survive an EMP OK, most of what seems to get fried in  
EMP events is wire coils and semiconductor junctions due to the  
enormous induced voltages (a good sized spool of wire in the crate  
wouldn't be a bad idea, spooled up wire exposed to an EMP tends to  
fuse into a solid block of copper if I remember corrrectly).

I'd say enough space to house a more or less universal Extra-class  
coverage HF radio, a versatile and low loss antenna tuner that can  
load up whatever you can scrounge (probably a random wire or dipole),  
and a good sized spool of suitable antenna wire if you can fit it in  
there, and count on leaving this setup packed away ready for use at  
all times (i.e. treat it as "emergency use only" and don't be tempted  
to dig it out and put it in the shack except for periodic  
functionality tests).  Probably better to use a less feature-rich but  
more rugged radio that will get you on the air with just the basics,  
to reduce the temptation.  :)

I wouldn't count on there being too many people out there to talk to  
after an EMP event, though, and I'd expect there to be really tight  
restrictions on who was and was not allowed to transmit even on ham  
frequencies for some time afterward.  So having a working transceiver  
may be of very limited use unless you're on record as belonging to a  
local ARES chapter and are handling disaster relief traffic ..

On Dec 14, 2007, at 1:11 AM, sco at sco-inc.com wrote:

> Has anyone thought about the idea/need/way to safeguard a few ham
> radio sets in an area in case of EMP? A nuclear device set off above
> ground will wipe out all modern electronics (ham sat radios) within a
> large distance from the epicenter. Even if the radios are outside the
> blast and radiation areas they would be useless because of the EMP
> (electro magnetic pulse). I would think that HS might be willing to
> fund a way to create some safe rooms to store some ham gear around
> the country. Perhaps even a large "safe box"? Ham satellite gear
> should be in this category.
>
> Les W4SCO

HAH, YES. HE ACTUALLY SAYS IN HIS LETTER, "I BET YOU DON'T EXIST 'COS  
EVERYONE KNOWS ITS YORE PARENTS." OH YES, said Death, with what almost  
sounded like sarcasm, I'M SURE HIS PARENTS ARE JUST IMPATIENT TO BANG  
THEIR ELBOWS IN TWELVE FEET OF NARROW UNSWEPT CHIMNEY, I DON'T THINK.

(: HAPPY HOGSWATCH :)