[RTTY] Minority Opinion on Cluster Spots

[Richard Kriss, AA5VU]

> Again, it's part of the game.  And as operators, we should be keen that if we
> don't see the station on the spotted frequency - turn the VFO!!!
> 
> 73, Don AA5AU

I agree with Don.  You can't work them unless you can hear (and print) them.
I don't recall finding many RTTY stations on the spotted frequency (mark or
otherwise).  I take the cluster spots as a pall park and start tuning from
there until I hear and print the station.

Soapbox:  I have asked many times about the VFO frequency displayed by the
other station and don't recall ever getting an exact match - even from
someone using the same Kenwood TS-570D(G). This is probably due to various
filters used and has nothing to do with calibration or accuracy of the rig
displays. I am not too concerned with accuracy of RTTY spots; however, I
would like to be able to post spots so others can find the signal.  The
issue is do you spot the frequency on your display where you heard and
printed the station or a calculated mark frequency?  This is not an issue
for operators with high-end rigs, like the FT-1000MP. I understand this
class of rigs adjust the readout to display the mark frequency and the
operators feel the low end rig users should adjust to the mark frequency to
be consistent. I really don't understand the obsession with the mark
frequency.  As I recall from the old days many of the green key machines
were left on auto start (can't remember the term) and would wake up when
called by a net station. It was very important to know the mark frequency to
be sure you were in sync. Those days are history... like paper tapes and
RTTY art. 

There is nothing in the manual for my Kenwood that says the VFO digital
display is adjusted for the mark so I am suppose to mentally subtract 2125
Hz from the frequency display reading then round it off because the clusters
only take one decimal point (14.085.00 MHz tuned display frequency reading
less 2125 Hz = 14.082.875 posted on cluster as 14082.9). This may the
accepted correct procedure; however, I personally prefer having cluster
postings to the VFO display frequency rather than some adjusted mark display
reading but anything close is okay with me.  One thing about RTTY is you
cannot work them unless you can print them and all signals need to be fine
tuned. Don, AA5AU, said it very well - turn the VFO!!!

To add to the above confusion and controversy over the mark my Kenwood
TS-570D(G) has a mode called LSB-FSK unlike the high end rigs that have a
RTTY mode switch. Yes, that is correct -the Kenwood display reads LSB-FSK
and USB-FSK or normal FSK.  The receiver in the TS-570D(G) is damn near deaf
to digital signals in normal SSB LSB or USB modes; however, the receiver
comes alive to digital signals in the FSK mode. Until recently I only used
FSK only for RTTY with a PK-232.  Due to orphaned AEA MacRATT software it
became time for me to come over to the dark side (sound card technology) and
use the Kenwood LSB-FSK (AFSK) mode . This mode is activated by Menu Item
#32 Filter Bandwidths for Digital Modes with options for 1200, 300,  P for
PSK (that works great for RTTY) and OFF (for normal SSB).  I have no idea
what, if anything, this mode does to the display reading. As noted above I
assume it is not adjusted like the high end rigs.

With all that said I agree with Chen, W7AY, who said ".... I think PSK31
PacketCluster spots are way more broken than RTTY spots".  RTTY is not a big
problem; however, finding and picking specific station from a spot taken
from another operator's waterfall display has all kinds of issues.  One of
the spotting issues is should you spot the adjusted frequency or dial plus
an adjustment in the notes?  I have seen cluster postings like 14070.0 with
a note saying PSK +1300 Hz rather 14071.3.  I wonder how the high end rigs
adjust or compensate the display readings for BPSK signals.

So much from a low end rig operator that tunes-to-print and is not too
concerned about the exact frequency.  If DX and Contesting was easy most of
us would lose interest.  Happiness is still making the contact!

Dick, AA5VU