[amsat-bb] Re: Russian speaking QRM on AO-51 Rev: 13642

[Tony Langdon]

At 08:21 PM 2/3/2007, you wrote:
>--- Justin Burket <zorton at jtan.com> wrote:
>
> > Chalk this e-mail up for another vote to reactivate the PL tone.
>
>But your email shows the reason why we don't want PL tones on ANY satellite.

Agreed.  The only reason the tone would be useful is to save Tx 
power, by having the Tx shut down when there is no valid uplink (like 
a terrestrial repeater).

We also have severe QRM issues on 2m uplinks, in our case, cordless 
phones from Indonesia and surrounding areas, which wipe out 2m 
uplinks then the satellite is north of Australia.


>PL tones don't cure the problem they hide it so we can shut our eyes and
>pretend it doesn't exist. The satellite is still unavailable for low power
>users, you have to transmit high power to overcome the interference so the
>satellite can hear you. PL tones aren't magic cure-alls.
>
>Since AO-51's tones been turned off we've got a far better understanding of
>what the situation is really like in different parts of the world. Unless we
>have the inform necessary to understand the problem there is no way 
>we can even
>to begin to start resolving it.

UO-14 was exactly the same.  For this part of the world, the answer 
is to go U/V instead of V/U.  This not only solves the QRM, but it 
also balances the uplink and downlink budgets for typical terrestrial 
stations giving satellites a go for the first time.

73 de VK3JED
http://vkradio.com