[NSRCA-discussion] curious - Transmitter Specs...

[Bob Kane]

I still play LP's . . . . . . none of that chopped-up digital for me, analog forever !!!!!

Bob Kane

getterflash at yahoo.com

--- On Tue, 3/23/10, Atwood, Mark <atwoodm at paragon-inc.com> wrote:

From: Atwood, Mark <atwoodm at paragon-inc.com>
Subject: Re: [NSRCA-discussion] curious - Transmitter Specs...
To: "General pattern discussion" <nsrca-discussion at lists.nsrca.org>
Date: Tuesday, March 23, 2010, 3:05 PM




 
 






All of this seems very reminiscent of CD’s first coming to
the market. 

   

New technology invariably brings a shift in the metrics and
specs that we use to evaluate it.  So yes, Latency is the new holy grail,
but that’s probably accurate. 

   

Quick rewind.  Prior to CDs, shopping for stereo equipment
was all about reading the specs, Total harmonic distortion, Signal to Noise
ratios, blah blah.  Good specs (for the most part) meant good sound. 
And as with all multi component systems, quality depended on the lowest quality
component in the system.  A great amp was only as good as the speakers it
was driving…and so forth. 

   

Then came Compact Discs, and initially, people were still looking
at Signal to Noise ratios on CD players.  It took a few years before it
set in that the signal to noise ratio was SO high (unlike a phono or tape deck)
that even the crappiest CD players had Signal to Noise ratios that were far
superior to anything the human ear could hear and THD that was for all
purposes, zero.   On the other hand, new specs DID add value.  Sampling
rate, digital to analog conversion rates, etc, became the new measures by which
to purchase.    As these have evolved, even those became
meaningless to all but the extreme audiophile as again, even the cheapest
players had specs that exceeded our ability to hear the difference. 

   

We have the same phenomenon occurring in our hobby.   
Latency is a new measure for all intents and purposes, since in there was
little variability in the PPM and AM days.    

   

I would argue to all that resolutions above 512, and certainly
above 1024, are no longer the weakest component in the system.  Slop in
our servo gears and  control linkages, even the best ball bearing ones,
still exceed that of a single point of resolution at 1024.   
That’s good news.   Just like with CD’s, it means even
the less expensive radios now have resolution that exceeds our needs.   

   

Latency has become a concern only because the early versions of
2.4 had some high latency.  I can NOT knock pioneers who pave the way for
the rest to follow and improve on.   We only have faster systems because
they brought the first “slow” ones to market and gave us a starting
point. 

   

But we’re quickly approaching the point where IMHO, latency
will be just as irrelevant as resolution in that all the systems will be faster
than we’re able to perceive and discern any difference. 

   

Yeah, there will always be those that purchase on the technical
superiority of a product, but practically speaking, they’ll be
equals.      

   

Ok, that’s my $0.02 

   

I think I’ll go play an album… 

   



Mark
Atwood 

Paragon
Consulting, Inc.  |  President 

5885 Landerbrook Drive
Suite 130, Cleveland Ohio, 44124  

Phone:
440.684.3101 x102  |  Fax: 440.684.3102 

mark.atwood at paragon-inc.com
 |  www.paragon-inc.com 



   





From:
nsrca-discussion-bounces at lists.nsrca.org
[mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of Bill's
Email

Sent: Tuesday, March 23, 2010 12:45 PM

To: General pattern discussion

Subject: Re: [NSRCA-discussion] curious 





   

Andrew Jesky wrote:  

I’m with you on this one Mark, I could notice the latency
a little bit in some systems but the servo grouping is nothing that I can tell.
I think the guys that really see this are the heli guys. I have talked to many
of them and they do tend to tell me they can “feel” the difference.
They are using much more servo throw all the time between positive and negative
collective as well as cyclic.  

  

Andrew 

  





Andrew is right, this all got started with the heli guys who flew CCPM. On a
big plane grouping is noce just to minimize servo stress and current draw, but
it is not something you are going to feel while flying. And in a glider the
only thing I ever work hard on matching is that the flap throw is matched
through the entire range of movement.



Like I said, a couple of years ago nobody even heard of latency, now it is the
Holy Grail.









 



 


-----Inline Attachment Follows-----

_______________________________________________
NSRCA-discussion mailing list
NSRCA-discussion at lists.nsrca.org
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion


      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20100323/4f24357b/attachment.html>