Re: [ARSCLIST] Internet audio: What do you expect of it ?

[phillip holmes <insuranceman@xxxxxxxxxx>]

Yes, EMP will scramble transistor based equipment.  That's not to say 
that the military hasn't taken steps to harden the equipment to EMP.  
All aircraft used by the military have been hardened, and I would assume 
that most other critical devices are also shielded to protect them.  
Anyway, tube stuff shrugs it off like it didn't even happen.  It's easy 
to explain, too.  The very small junctions in transistor stuff are easy 
to break down with an over voltage.  This is one of the reasons that 
transistor stuff will just mysteriously stop working.  You should see 
what kind of spikes are on the AC lines.  And there's also static 
electricity that can be in the thousands of volts.  On the other hand, 
tubes are primarily thermal devices and need to be really abused to be 
destroyed.  The only thing I could foresee that would destroy a tube in 
a nuclear scenario is arching from the cathode to the anode during the 
voltage spike.  I'm sure one of the reasons there are gas voltage 
regulator tubes and huge chokes in FAA and military equipment is to 
prevent those spikes from reaching the signal tubes.  Also, the power 
supplies in tube equipment seem to respond to changes in line voltage 
slower than transistor stuff, just from my observations while working on 
the things.  At the very worst, you just replace some of the tubes and 
you're back in business.  Not so with a complicated microprocessor based 
machine.  Also, the FAA has a large cache of tubes (or they did a few 
years ago).  
Phillip

Don Cox wrote:
> On 23/12/07, phillip holmes wrote:
>   
> > Actually, the Western Electric tubes are produced here in the US. We
> > still have the capability to produce high quality tubes, but at a very
> > high price.
> >     
>
> I believe tubes are still being produced (and used) for military
> electronics, as they are more resistant to nuclear effects than
> transistors.
>
> Regards
>