Good points, Jeff and Ed. Certainly, there's no benefit in moving
someone to 14091.13 rather than 14091.1.
One part of this is the old "accuracy vs precision" conundrum. Doesn't
do much good to report frequencies with 10-Hz precision if the
frequencies are 120 (or whatever) Hz off. On the other hand, if you log
spots from stations with GPSDO or TCXO and compare their spots with
yours, you should be able to adjust your QS1R clock to get closer than
that. Then, of course, the other problem is oscillator stability; I
don't know of either a quoted spec or measured stability of the QS1R's
internal clock, but I do know the receiver gets hot inside.
73, Pete N4ZR
Download the new N1MM Logger+ at
<http://N1MM.hamdocs.com>. Check
out the Reverse Beacon Network at
<http://reversebeacon.net>, now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.
On 10/14/2015 3:15 PM, Jeff AC0C wrote:
There are several issues being comingled here.
I think that the absolute accuracy of the spot is more important. If
you are running S&P assisted, and the spots are accurate, then with a
tight AFC you don't have to hunt and rate is higher. So in this case
the 2nd DP is a benefit here. But if the spot tolerance is already
sloppy, then a 2nd DP is of no benefit.
As for the length of the pass frequency resolution, that's something
that the logger should really let you specify because in RTTY, 0.1 may
be FB but the same logger running CW probably would want that 2nd DP.
Of course Ed is THE MAN and so I will definitely take his word that
0.X is better in RTTY than 0.XX.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-----Original Message----- From: Ed Muns
Sent: Wednesday, October 14, 2015 1:59 PM
To: 'Pete Smith N4ZR'
Cc: 'RTTY Contesting'
Subject: Re: [RTTY] Contester preference - 1- versus 2-decimal-place
spots
Any spot should simply be a starting point to tune in, copy and
validate the
transmitting station's call sign. In less than 30 minutes, a new RTTY
operator should be able to develop the skill to tune in a signal by
ear to
within 10-20 Hz in a second or two. No different than zero-beating on
CW by
ear. That's good enough for most RTTY decoders.
Therefore, 2-decimal point spots are overkill and distracting. The
operator
has to ignore/discard/round off the second decimal position if manual
tuning. Automatic spot tuning has no benefit from the second
decimal. One
decimal point is plenty of resolution for finding and IDing a spot.
For the
same reasons it is the optimum resolution for passing a QSY frequency,
i.e.,
either 14083.7 or 14083.8 is better than 14083.76.
Ed W0YK
-----Original Message-----
From: RTTY [mailto:rtty-bounces@contesting.com] On Behalf Of Pete
Smith N4ZR
Sent: 13 October, 2015 18:44
To: RTTY Contesting
Subject: [RTTY] Contester preference - 1- versus 2-decimal-place spots
I'm doing some analysis of RTTY spots made by RBN nodes reporting 2
decimal place frequencies. Some of them I know to be using GPS
disciplined oscillators, while others aren't. The GPSDO stations
generally agree within 10 Hz, and are probably better than that because
of rounding errors. The others are surprisingly good, almost always
within the +/- 0.1 KHz we seek generally from RBN nodes.
My questions: Do assisted RTTY contesters like to get 2-decimal spots?
Or are they so used to 1-decimal spots that they automatically joggle
tuning to get on the proper mark and space frequencies?
And... are inaccurate 2-decimal spots (still within +/-1-decimal
tolerance) worse than 1-decimal, or essentially the same from an
operational perspective?
73, Pete N4ZR
Download the new N1MM Logger+ at
<http://N1MM.hamdocs.com>. Check
out the Reverse Beacon Network at
<http://reversebeacon.net>, now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.
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