[ICOM] IC 756PROII value?

[Jens Schmidt]

Hi Adam,

I had the impression that an EMP event would do its damage by inducing
unintended / unacceptable voltages / currents into conductors, thereby 
frying the transistors.
Vacuum tubes would just arc, and possibly survive.

Radiation hardening is intended to protect against energetic particle
impacts, so we should not place those U238 paperweights on top of our
solid state Icom transceivers.

73 Jens

Adam Farson wrote:
> Hi Clete,
> 
> By the same reasoning, the Soviets used tubes in all their mission-critical
> electronics (e.g. in combat aircraft and even in missiles) for many years.
> However, component engineers did not stand still; they went on to develop
> radiation-hardened semiconductor devices.
> 
> By the time the old vacuum-tube sets were finally taken out of mothballs,
> many capacitors and other components inside them had deteriorated to such an
> extent as to render repairs uneconomical except by dedicated amateur
> restorers. The manufacturers had long ago ceased production of those sets.
> 
> "In technology, there are but two degrees of freedom: forward and down.
> There is no backwards."
> 
> Cheers for now, 73,
> Adam VA7OJ/AB4OJ
> 
> 
> -----Original Message-----
> From: icom-bounces at mailman.qth.net [mailto:icom-bounces at mailman.qth.net] On
> Behalf Of C.Whitaker
> Sent: 16-Jun-10 08:54
> To: ICOM Reflector
> Subject: Re: [ICOM] IC 756PROII value?
> 
> de WB2CPN
> I suppose not many know this, but way back in the '60's when transistors
> were coming in, DOD had a real fear that an atomic detonation at a high
> altitude over the US would destroy a great many communications facilities if
> they used transistors in critical circuits.   DOD gathered
> up all the tube type transceivers, such as the Collins S-Line,
> and stashed them inside the mountain in Colorado.   It
> was years later that those radios finally got into the military MARS
> channels.
> 73  Clete
>