[CQ-Contest] Summarizing the Skimmer Accuracy Thread

[Marijan Miletic, S56A]

N4ZR wrote: The two QS1Rs (out of over 60 regulars contributing to the RBN)
continue to baffle us.

 

I spent some Excell time with 150K RBN raw spots from quiet Feb. 26th.  I
didn't find any harmonics error. 

 

Other obvious error examples within first 5000 QSO included:

 

ON5KQ ON         EU          7033,7   40m       2E0VMT               G
EU          CQ          27           26.2.2013 19:52 40m

ON6ZQ ON         EU          7022,3   40m       2E0VMT               G
EU          CQ          20           26.2.2013 19:52 40m

DF7GB  DL           EU          7033,7   40m       2E0VMT               G
EU          CQ          16           26.2.2013 19:52 2E0VMT

This is probably classic QSD case?

 

OL5Q     OK          EU          14020,5 20m       4S7WI   4S           AS
CQ          40           26.2.2013 16:21 20m

OL5Q     OK          EU          14005,0 20m       4S7WI   4S           AS
CQ          24           26.2.2013 16:22 20m

RU9CZD                AS           14005,1 20m       4S7WI   4S           AS
CQ          7              26.2.2013 16:22 20m

I guess OL5Q has too much gain although image seems to be 16 dB stronger
than real signal.

 

SV8RV   SV           EU          7046,1   40m       5E5ET    CN          AF
CQ          14           26.2.2013 15:44 40m

F5VLY    F              EU          7046,0   40m       5E5ETT  CN
AF           CQ          23           26.2.2013 9:16    40m

F5VLY    F              EU          7046,0   40m       5E5ETT  CN
AF           CQ          20           26.2.2013 10:13 40m

TF3Y       TF           EU          7046,0   40m       5E5ETT  CN
AF           CQ          19           26.2.2013 20:18 5E5ETT

Dots artifact but always on 7046 kHz at various times and places.  It might
be SSB signal.

 

S52AW  S5           EU          14081,5 20m       A5TN     A5           AS
CQ          20           26.2.2013 10:05 20m

S52AW  S5           EU          14081,5 20m       A5TN     A5           AS
CQ          19           26.2.2013 10:08 A5TN

Others spoted UT5MD at 14080 kHz at the first case, second 3 minutes later
is misterious as UT5MD moved to 18 MHz.

 

QS1R operates with 16 bit ADC and discrete errors caused my arithmetic might
be expected.  Similar RX problems with DDS are cleaned by analog PLL.

 

N1MM Logger window for Available mults & QSOs highlights most of the bad
uniques better than overcrowded bandmap.

 

LP MMM S56A