[Elecraft] QRP signals from Pathfinder probe (off topic)

[Matthew Cook]

Lets not forget to include Madrid (Spain) and Canberra (Australia) in the
above story, without them Goldstone cant do it on it's own.  One station
may start the transmission, but every 8-12hrs each station seamlessly hands
over to the next to provide continuous coverage at the earth rotates.  It's
even more important for Voyager with a transmission path of 18 hours, now
that is mind blowing stuff.

73

Matthew
VK5ZM

On 17 July 2015 at 04:28, Fred Townsend <fptownsend at earthlink.net> wrote:

> Mike You can do the math for path loss. The formulas are well known.
> Perhaps less known is the rest of the story. The probe is using its high
> gain (dish) antenna, perhaps 20 db. Since it is a dish antenna it must be
> aimed! The probe is programmed to aim its antennas periodically since it
> can not be commanded to turn its antenna.
> Back at this end, the Goldstone antennas have about 60db gain with
> cryogenically cooled noise figures of <1. I'm guessing the receiver
> sensitivity at around ---150 to -170 dbm using a very narrow bandwidth and
> correlation techniques similar to what is used on GPS receivers.
> Transmission flight of path is > six hours.
> 73
> Fred, AE6QL
>

<SNIP>