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Re: PSK, what is BPSK? Fourier escapes me at the moment.



Christopher,

I know exactly what you mean! Although I majored in Electronic Engineering
and Math, albeit 15 years ago, my career took me to software, and for a good
deal of that I wrote assembly language (about as dead as a TNC now).

The hardware now is so cheap for mucho MIPS (should that be GIPS?), and is
so reliable, software is indeed the way big industry goes. Problem is I
wouldn't have a clue where to start programming a DSP chip.

With mega bucks and big development departments of course you can program
all sorts of DSP stuff - and actually _produce a result_ which works. But I
think it takes that. I don't see many Hams with the sort of background and
bucks which would endear or even allow them to spend sufficient time to get
this done in the shack. And actually then have the time to have a QSO!

There is however a big difference between hardware and software. Hardware's
easy to debug and fix, but software's not.

At another level I see this at work in my job as freelance troubleshooter
for trading systems day after day... it's really rare to have a catatrophic
hardware problem. There's always an immediate offsite backup with comms for
critical systems. But if your software's wrong (embedded as well as
application) it's always a workaround. There's no such thing as a quick
reliable fix in software.

The G3RUH 9600 bps modem was the last of its breed. A great hardware
solution. Zero MIPS. Lots of jumpers. It works. Well. And I can pop the
'scope on it if I don't know what's going wrong. Care to try doing that with
a DSP?!

73 Howard G6LVB

----- Original Message -----
From: "Christopher Cox" <cobox@urec.net>
To: "laura halliday" <marsgal42@hotmail.com>; <amsat-bb@AMSAT.Org>
Sent: Saturday, September 09, 2000 2:12 PM
Subject: [amsat-bb] PSK, what is BPSK? Fourier escapes me at the moment.


> >
> > TNCs? I remember reading about those in history books.
> >
> > All modern implementations are based on DSP, with all pro-
> > cessing done in software.
> >
>
> Well Laura, no reason to waist a few transistors where a few thousand
could
> do the job....:-)
>
> But seriously, being self taught, I understand comb filters and delta
> filters, but Fourier escapes me at the moment.
>
> You mentioned that BPSK may be difficult to track. I thought my DSP-2232
> would. What is the difference between BPSK and PSK another 90 degree
> signal?
>
> Later
>
> Christopher Cox
>
> ----
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