[hpsdr] What can we do with 2 cards

[Robert McGwier]

It does not need to be that complicated unless you want it to be that 
complicated.  My opinion is that we are seeing the natural fall out of 
people realizing that Atlas was the right first step.  It gave them a 
way to do myriad things and share the design trials and tribulations 
with this 'incubator group'.  No one has to do it all.  I do not think 
everyone should rush out and get every board until and unless you 
actually know what you are going to do with it.  Insofar as this advice 
goes,  Cecil and I agree.  The "Whole Magilla"  is not for everyone.

On the other hand:

If you want N channels of phased arrays on 435 MHz,  2.3-2.4 GHz,  and 
5.6 GHz,  I suggest you need to (more than one each) OZY, Mercury, 
Sasquatch, and a Gibraltar for phase coherent oscillators, the Sasquatch 
running control algorithms, and you had better plan on some RF talent in 
front of it.  With the huge memories in our computers and the 160 meter 
band being only (effectively) 100-150 kHz wide,  we can do a four square 
without phasing lines (we will need a little TDL because 100000/1800000 
 > 0.01 so we cannot just pseudo steer with oscillators).

If you want an envelope elimination and restoration transmitter,  you 
probably are going to want an Sasquatch,  maybe Jason,  and you better 
know how to build a Class E amplifier chain and a class S modulator 
chain (switching power supply,  pulse width modulators, etc.) and then 
hope we can predistort the phase and modulator channels in Sasquatch to 
make everything very linear (or not if you want nonlinear).

I am not saying this stuff for any reason other than to show how I would 
use the stuff as an example if "things go right".   If you don't have 
this level of specificity in your requirements, then you probably don't 
need all this stuff until more algorithms are done and some assembly 
experience is acquired because there is quite a bit of difference in the 
all powerful super capable,   show stopping wonder and amazement at 
fancy news toys and having them actually do it.  I would not buy Atlas, 
OZY, Mercury, Gibraltar,   Sasquatch and a few hundred dollars in 
REQUIRED assembly tools (minimum) and then be prepared to sit and stare 
at it in wonder and amazement while you await some other coding wizard 
to do the job.  Assembling these boards is not going to be for the 
average ham with the now average age approaching shaking hands, fading 
memories, and failing eyesight (everyone else is just catching up to me  
;-) ).  This is fun but there are quite a few hours of work to make this 
useful.

Bob


Now, I am not saying this

kd5nwa at cox.net wrote:
> ***** High Performance Software Defined Radio Discussion List *****
>
> That was the original plan, a two board system to connect to a SDR
> transceiver, but it's gotten too complicated since then, that why I
> bailed out. Soon at the rate it's going, you going to need 4 to five
> boards to run the radio, that will be rather an expensive solution to a
> simple problem. With a two board system, you can still add other boards
> for more specialized projects, but boys love they complicated toys.
>
> Good luck.
>
>
>
>   


-- 
AMSAT VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats,
NJQRP/AMQRP, QRP ARCI, QCWA, FRC. ARRL SDR Wrk Grp Chairman
Laziness is the number one inspiration for ingenuity.  Guilty as charged!


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