media what died a'bornin'

From: John Lawson <jpl15_at_panix.com>
Date: Thu Oct 7 14:14:52 2004

On Thu, 7 Oct 2004, Dwight K. Elvey wrote:

>> From: "Vintage Computer Festival" <vcf_at_siconic.com>
>
> ---snip---
>> There was also a discussion about bouncing signals off the moon to create
>> a delay-line memory of sort.
>>
>> What if we were to preserve software by encoding it as audio and bouncing
>> it off the moon? I figure we could probably save a few old programs that
>> way :)
>>
>
> Hi
> You'd need a few different frequencies. The round trip to
> the moon and back is only 2.6 seconds. It would be much more
> reliable if there was a repeater on the moon otherwise the
> signal would be weak.
> Dwight

   You'd need a way to overcome the severe phase-rotation and libration
fading artifacts that make Earth-Moon-Earth reflection-mode communications
a peculiar (and rather frustrating) hobby for us Hams.

   Folks use large, high-gain (10 meter > up) dishes, and legal-limit
output powers (1500Watts at 450 MHtz) and specialized communication
algorithms, like phase-coherent Morse Code, in order to actually send
'intelligence' - even using a keyed unmodulated carier, the throughput is
byte-per-minutes.

   Have to use a whole lotta wait-states for the EME buffer...


Cheers

John
Received on Thu Oct 07 2004 - 14:14:52 BST