[eagle] Re: 70 cm Eagle Receiver - Final Spur Report (at least for today...)

[Bdale Garbee]

On Sun, 2007-06-17 at 08:48 -0700, Juan Rivera wrote:

> I've completed my testing and analysis of the spurs that appeared in
> the IF output of the 70 cm Eagle Receiver prototype.  I believe I know
> the source and the cause of all of them and how they can be eliminated
> or rendered harmless.

Nice work.

Reading your report, two things strike me, neither of which I consider
myself an expert on in AMSAT or elsewhere, but both of which I'll
mention to help motivate the review of power system requirements you
clearly hope comes next/soon.  

The first is that I think AMSAT does understand most if not all of the
issues you're warning against regarding DC distributiong wiring.  Some
care was taken, for example, in planning pinouts of the 15-pin connector
on the spacecraft bus side of the CAN-Do! widget, and in the proposed
wiring harness design from the Black Forest meeting.

The second is that I think more work is going to be required to ensure
receivers behave reasonably in the presence of supply noise.  For
various reasons, as others have already alluded, I wouldn't count on the
Eagle power bus being very quiet.

Bdale, from Edinburgh