[amsat-bb] Re: AO-16 report

[Clare Fowler]

Some more observations.
Clare VE3NPC

----- Original Message ----- 
From: "OZ1MY" <oz1my at privat.dk>

> I do not know about other areas of the World - but here
> over Europe the background noise on the downlink is very high.
> Did not experience the normal FM quieting effect by increasing the
> uplink power. I do not understand that - any ideas ?
> Is AO-16 making the noise itself ??

Yes the noise is coming from AO-16 and is readily observed on
my home brew spectrum display unit.
Its amplitude (QSB) varies at a cyclical rate of about 14 seconds 
which corresponds to a spin rate of close to 4 rpm.
The peak to min on my FT-847 can be up to 6 S units depending
on elevation distance and angle with the maximum difference 
occurring at higher elevations. 
>

> The polarity of the downlink antenna is difficult to make out.
> I thought it is RHCP - but Mark says LHCP.
> For me on the passes to the East RHCP is best !
> Passes from the South - LHCP is best !
> That is a general observation - some times it helped to switch
> during the passes.
> AO-16 might be tumbling a lot ?

My observations agree with this as the sat approaches and 
recedes. However during the middle of a high elevation pass 
when one polarity is at a minimum the opposite polarity is at a 
maximum.  I have 2 x 10 turn helix ants on RH and a single
10 turn helix on LH with coax relay switching. 

>
> Have fun and thanks to the team and the builders.
>
> 73 OZ1MY
> Ib
>

VE3NPC
Clare