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RE: [linrad] Second operator

Hi Sigurd and All,

> I also would think the broadcasting of data from the primary 
> computer to one
> or more computers by using  "sockets", as suggested by another 
> e-mail, would
> be a good approach.  It would allow more flexability in how the secondary
> computer might process the A/D data.
Yes. The current network implementation is silly - but it was easy
to implement.

I do not want to go deeply into various network protocols and
I do not really know what "socket" stands for. Presumably the
network contains a lot of things I will never want to know;-)

Linrad needs to open something. A "socket" or something else, to
which it can write data freely. The master does not want to know
what happened to the data, the place to where it writes just has to
be able to "swallow" big enough chunks of data at a high enough speed.

The slave has to open something from which it can read sequentially
and the slave has to be able to ask how many bytes there are that
can be read immediately. The place from which it reads must be capable
of buffering up about 1 second of data. 

The current network operates like this and I make no use of the
fact that the computers are "connected".

> > I am not sure I understand what you are doing, but it sounds 
> interesting.
> > Am I correct in assuming that the primary computer is doing the A/D
> > conversion and "most" of the digital signal processing and the secondary
> > computer is being used primarily for a display? 
No. This is not correct at all. The primary computer does the A/D 
conversion and it can be set to do the first step of processing,
the first fft. 

The intended usage is that the primary computer runs with the first
operator and presents the station he wanted to listen to to his
headphones while showing the spectrum to the first operator the way
he wants. Perhaps with a rather zoomed in display to give more detailed
view over the stations in a pileup.

The second operator may have different preferences. He may want to
look around for CQ callers and to check what the competitors are working
so he may want the full spectral range.

Buth computers will have to run the second fft because it is influenced 
by what frequency the operator currently wanted to his headphones and
what bandwidth he is listening at. 

> For example,  could I use
> > my 1.8 GHz P4 computer for the primary computer, w/o any 
> display, and use my
> > 255 MHz PII laptop for a display?  this might be attractive for a
> > microwave rover.
I do not understand why. Why not use the 1.8 GHz P4 for everything
while using the laptop for logkeeping etc.

Now, for microwaves I guess you do not need the noiseblanker. Then
the primary computer will do essentially all the heavy processing
because there will be no second fft.

Still, why use two computers if you are a single operator?
Maybe I am missing something;-)


Leif  /  SM5BSZ