[sarex] Re: further late reply regarding ISS simplex
ransomk at yahoo.com
Fri Aug 11 19:42:16 PDT 2006
Split operations allows everyone can hear the
astronauts talking back all the time.
Kenneth - N5VHO
--- McGrane <tmcgrane at suffolk.lib.ny.us> wrote:
> Hello again- the astronauts will hear everyone
> calling whether its split
> or simplex operation so why not make it simplex!
> On Fri, 11 Aug 2006, Ransom, Kenneth G.
> (JSC-OC)[BAR] wrote:
> > It sounds like your issue is not that split
> frequencies are bad but that
> > multiple uplinks makes it difficult for the crew
> to listen to one
> > uplink. ITU region regulations for ground station
> operations are the
> > culprit. Space has no borders but Earth does so
> have of the problem is
> > getting everyone to agree on a single uplink. Not
> everyone in the world
> > has the same frequency allocations nor do they use
> the available
> > spectrum in their region the same way.
> > The issue is not the 20-30 miles but the number of
> callers in the 2000
> > km wide footprint. The station has to listen to
> all of them. Since you
> > can't hear all of them, it becomes difficult to
> know when someone is
> > talking or not without guidance from the station
> > In the MIR days, the crew did not have the luxury
> of near full time
> > satellite communication that provides voice, email
> communication and an
> > IP phone that lets them make phone calls. If the
> MIR crew wanted to talk
> > to someone, they needed to use the ham radio or
> the Russian VHF space to
> > ground system. The ISS crew has plenty of options
> to choose from when
> > they want to communicate and it depends on the
> personality of the crew
> > as to which ones get utilized.
> > Kenneth - N5VHO
> > -----Original Message-----
> > From: sarex-bounces at AMSAT.Org
> [mailto:sarex-bounces at AMSAT.Org] On Behalf
> > Of McGrane
> > Sent: Thursday, August 10, 2006 6:43 PM
> > To: Manned space BBS
> > Subject: [sarex] further late reply regarding ISS
> > Greetings from patrick N2OEQ
> > Despite support of the present frequency scheme
> for the ISS I still wish
> > to disagree with the policy of split operation
> with different phone
> > uplinks.
> > Back when the MIR was up, the russians operated
> simplex and left the
> > radio on to listen for callers.
> > On several occasions, I called the MIR according
> to my tracking program
> > and was rewarded several times with a response.
> > With two different uplink frequencies, the
> astronauts are less inclined
> > to leave the radio on to listen for callers.
> > When there were several callers here on simplex
> responding to a CQ call
> > from the MIR, we acted civilized and took turns
> and everyone made
> > contacts so I dont buy the absolute need for split
> > Besides, how many callers could there be within 20
> or 30 miles up to the
> > horizon.
> > We've had years of robot like amateur radio on the
> ISS. How about
> > loosening the ties!
> > Thanks for the soapbox..... pat
> > ----
> > Via the sarex mailing list at AMSAT.ORG courtesy
> of AMSAT-NA.
> > To unsubscribe, visit
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