On Nov 11, 8:57*am, "D. Peter Maus" wrote:
On 11/11/11 24:15 , wrote:

On Nov 11, 12:04 am, David
wrote:
My guess is that the cost you would have to charge to recoup the time
and effort you put together in coming up with such a design would end
up making such a set *much* more expensive than just going to a ham
fest, buying a Hammarlund in good shape, and fixing it up. Or even
paying someone else to fix it up.

* I already have a R-390, two Hammarlunds and a Racal....I wanted to
manufacture something. Or at least think about it.

* *Certainly worth thinking about.

* *Maybe worth doing. But consider:

* *Tubes are getting harder to come buy. Not that they can't be had.
And after an EMP, they're likely to be as available as working SS
devices. But there are inherent issues with Tubes. One is that they
use a LOT of precious energy, that in a survival mode situation is
best conserved for other applications, or longer listening. Another
is that voltages are much higher than those that can be recovered
after or during a crisis with ease. Low voltage, low current devices
are going to be more desirable when energy is in short supply.

* *But, more importantly, tube receivers aren't necessarily less
prone to damage by EMP than SS receivers. In fact, there is
empirical evidence to suggest that SS receivers can be made to
survive an EMP where a tube receiver will not.

* *Your best options, then, would include building a reasonably high
performance receiver with readily available common parts, and take
measures, such as a Faraday cage, and effective grounding/input
protection measures, to render your station if not immune, then more
resistant to stray or induced hostile voltages.

* *Now, you have a practical, and manufacturable, product.

-wrt- Faraday Cage :
Old Metal {Steel} Garbage Can with a
tight fitting Lid. -store-holding-
+ The Solid State AM/FM/SW Radio
+ Plenty of Batteries
-or- Re-Chargeable Batteries and a
Solar Charger

-no-tubes-required- ~ RHF

On 11/11/2011 10:10 PM, RHF wrote:

...
-wrt- Faraday Cage :
Old Metal {Steel} Garbage Can with a
tight fitting Lid. -store-holding-
+ The Solid State AM/FM/SW Radio
+ Plenty of Batteries
-or- Re-Chargeable Batteries and a
Solar Charger

-no-tubes-required- ~ RHF
.

Satellites are withstanding these on an almost daily basis, for years,
if not decades ... doesn't seem to be a real problem anymore ...
however, laying hands to that technology might be a bit of a different
story ... as, while one nation might wants its' own satellites hardened,
it certainly doesn't want the enemies ...

Regards,
JS

On Nov 12, 2:44*pm, John Smith wrote:
On 11/11/2011 10:10 PM, RHF wrote:

...
-wrt- Faraday Cage :
Old Metal {Steel} Garbage Can with a
tight fitting Lid. *-store-holding-
+ The Solid State AM/FM/SW Radio
+ Plenty of Batteries
-or- Re-Chargeable Batteries and a
Solar Charger

-no-tubes-required- ~ RHF
* .

Satellites are withstanding these on an almost daily basis, for years,
if not decades ... doesn't seem to be a real problem anymore ...
however, laying hands to that technology might be a bit of a different
story ... as, while one nation might wants its' own satellites hardened,
it certainly doesn't want the enemies ...

Regards,
JS

As far as I know- none of the satellites are using vacuum tubes .
That's the reality .

wrote in message
...


As far as I know- none of the satellites are using vacuum tubes .
That's the reality .


--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

All satellites still use these for output:

http://en.wikipedia.org/wiki/Traveling-wave_tube

On Nov 12, 8:55*pm, "Brenda Ann"
wrote:
wrote in ...

As far as I know- none of the satellites are using vacuum tubes .
That's the reality .

---------------------------------------------------------------------------*-----
---------------------------------------------------------------------------*-----

All satellites still use these for output:

http://en.wikipedia.org/wiki/Traveling-wave_tube

Oh,sorry. But this may be a miniature tube for microwave frequencies .
Where do they obtain high voltages - it must be smps type . Solar
panels??

On 11/12/2011 6:59 PM, wrote:
On Nov 12, 8:55 pm, "Brenda
wrote:
wrote in ...

As far as I know- none of the satellites are using vacuum tubes .
That's the reality .

---------------------------------------------------------------------------*-----
---------------------------------------------------------------------------*-----

All satellites still use these for output:

http://en.wikipedia.org/wiki/Traveling-wave_tube

Oh,sorry. But this may be a miniature tube for microwave frequencies .
Where do they obtain high voltages - it must be smps type . Solar
panels??

NASA knows about voltage converters ...

Regards,
JS

On 11/12/2011 5:55 PM, Brenda Ann wrote:


wrote in message
...


As far as I know- none of the satellites are using vacuum tubes .
That's the reality .


--------------------------------------------------------------------------------

--------------------------------------------------------------------------------


All satellites still use these for output:

http://en.wikipedia.org/wiki/Traveling-wave_tube

Fact of the matter is, you don't need tubes in space, you already have a
much better vacuum than can ever be created on earth ... you simply need
the elements ...

Regards,
JS

On Sat, 12 Nov 2011 17:24:02 -0800 (PST), wrote:

On Nov 12, 2:44*pm, John Smith wrote:
On 11/11/2011 10:10 PM, RHF wrote:

...
-wrt- Faraday Cage :
Old Metal {Steel} Garbage Can with a
tight fitting Lid. *-store-holding-
+ The Solid State AM/FM/SW Radio
+ Plenty of Batteries
-or- Re-Chargeable Batteries and a
Solar Charger

-no-tubes-required- ~ RHF
* .

Satellites are withstanding these on an almost daily basis, for years,
if not decades ... doesn't seem to be a real problem anymore ...
however, laying hands to that technology might be a bit of a different
story ... as, while one nation might wants its' own satellites hardened,
it certainly doesn't want the enemies ...

Regards,
JS

As far as I know- none of the satellites are using vacuum tubes .
That's the reality .

Dream on. Just about every satellite in the sky uses vacuum tubes. The
TWT (travelling wave tube) is still the way to generate high, reliable
power for space-borne transmitters.

d

On 11/12/2011 11:12 PM, Don Pearce wrote:
On Sat, 12 Nov 2011 17:24:02 -0800 (PST), wrote:

On Nov 12, 2:44 pm, John wrote:
On 11/11/2011 10:10 PM, RHF wrote:

...
-wrt- Faraday Cage :
Old Metal {Steel} Garbage Can with a
tight fitting Lid. -store-holding-
+ The Solid State AM/FM/SW Radio
+ Plenty of Batteries
-or- Re-Chargeable Batteries and a
Solar Charger

-no-tubes-required- ~ RHF
.

Satellites are withstanding these on an almost daily basis, for years,
if not decades ... doesn't seem to be a real problem anymore ...
however, laying hands to that technology might be a bit of a different
story ... as, while one nation might wants its' own satellites hardened,
it certainly doesn't want the enemies ...

Regards,
JS

As far as I know- none of the satellites are using vacuum tubes .
That's the reality .

Dream on. Just about every satellite in the sky uses vacuum tubes. The
TWT (travelling wave tube) is still the way to generate high, reliable
power for space-borne transmitters.

d

They would be fools to attempt to boost the weight and fragility of
vacuum tubes into space, if they have any other alternative ... high
power is easily handled with the modern transistors ... the energy
requirements of the heaters is also another no-go ...

Regards,
JS

On Sat, 12 Nov 2011 23:42:22 -0800, John Smith
wrote:

On 11/12/2011 11:12 PM, Don Pearce wrote:
On Sat, 12 Nov 2011 17:24:02 -0800 (PST), wrote:

On Nov 12, 2:44 pm, John wrote:
On 11/11/2011 10:10 PM, RHF wrote:

...
-wrt- Faraday Cage :
Old Metal {Steel} Garbage Can with a
tight fitting Lid. -store-holding-
+ The Solid State AM/FM/SW Radio
+ Plenty of Batteries
-or- Re-Chargeable Batteries and a
Solar Charger

-no-tubes-required- ~ RHF
.

Satellites are withstanding these on an almost daily basis, for years,
if not decades ... doesn't seem to be a real problem anymore ...
however, laying hands to that technology might be a bit of a different
story ... as, while one nation might wants its' own satellites hardened,
it certainly doesn't want the enemies ...

Regards,
JS

As far as I know- none of the satellites are using vacuum tubes .
That's the reality .

Dream on. Just about every satellite in the sky uses vacuum tubes. The
TWT (travelling wave tube) is still the way to generate high, reliable
power for space-borne transmitters.

d

They would be fools to attempt to boost the weight and fragility of
vacuum tubes into space, if they have any other alternative ... high
power is easily handled with the modern transistors ... the energy
requirements of the heaters is also another no-go ...

Regards,
JS

Energy requirements are not a problem, and neither is G-loading on
takeoff. You are inventing problems where none need exist. TWTs are
mega-reliable devices with a very predictable life curve.

It is much more important to know exactly how long and how well your
satellite is going to work than to hope to get longer by using a
technology that might last longer, but will more probably die
unexpectedly when struck by a cosmic ray burst.

d