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Re: SDR-1000 (was FT-847 discontinued?)



If I recall correctly :
Quantizing any short duration signal to digitize it must be done fast
enough to be able to 
re constitute the signal again
Quantizing a CW dit requires high speed sampling .
Higher than SSB voice.    
I hope I am correct on this as it has been a long time ago that 
quantizing received radar pulses was an every day event.
Like you I am trying to grasp new ways and equipment idea's.

Keep trying 

Joe K0VTY
============================
On Thu, 15 Dec 2005 18:46:21 -0600 "John P. Toscano"
<tosca005@tc.umn.edu> writes:
> Dave G. wrote:
> 
> > The problem for high speed CW lies in the inherent delay with 
> > the DSP processing algorithms. IMHO because of that delay 
> > it's not yet a serious contest rig YMMV!!
> 
> Dave (or anyone else on the list who knows):
> 
> Is the "slow" CW speed only a function of computer-generated CW?  If 
> so, 
> couldn't you get around that problem by using an external keyer?  
> The 
> MFJ-495, for example, allows you to send CW via straight key, 
> paddles, a 
> PC keyboard plugged directly into it, or via a serial data stream 
> from a 
> computer.  It handles speeds up to 990 WPM (or so they say), which 
> oughta be fast enough for almost anyone.  :)  (Heck, if I could 
> reliably 
> work CW at a "mere" 20 WPM I'd be ecstatic!)
> 
> Or is the SDR not able to send fast CW even if it doesn't have to 
> synthesize the CW from keyboard commands on the same PC that is 
> supporting the digital encoding/decoding process?  It just seems odd 
> to 
> me that it could encode voice into an SSB or AM or FM signal, but 
> simple 
> "on/off" sequences of Morse code would be hard for it to do...  But 
> I'm 
> certainly very uneducated (at least so far) about the whole SDR DSP 
> process, so maybe I'm way off base...
> 
> If the problem is the delay between hitting the dit or dah side of 
> the 
> paddle and the time that you hear feedback from the monitor speaker, 
> it 
> should be possible to listen to yourself send only from the output 
> of 
> the keyer, and have the SDR not echo what you send back to your 
> ears. 
> Then, it doesn't matter if it takes an extra 300ms for your CW to 
> finish 
> transmitting before the person on the other end can respond.
> 
> Or am I still missing something totally?  (These are honest 
> questions, 
> I'm not trying to take pot shots at anyone, I really don't know the 
> answers to them.  Since I've been tempted to step into the SDR-1000 
> world "one of these days", I'd really like to know more about it.)
> 
> 73 de W0JT
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