‰  NOW 40 WPM  ‰  TEXT IS FROM MARCH 2009 QST  PAGES 89, 90 AND 81  ‰

ACCESS TO ITS 8 MHZ IF AT A POINT BEFORE FILTERING.  THUS IT IS POSSIBLE TO
OPERATE SDR SOFTWARE LIKE THE OPEN SOURCE POWER SDR WWW.  FLEX RADIO.  COM,
ROCKY WWW.  DXATLAS.  COM/ROCKY OR WINRAD WWW.  WINRAD.  ORG TO PROVIDE A
SPECTRUM ANALYZER USING AN EXCELLENT OFF
‰  FROM PAGE 81  ‰
273,105 B C W9IIX 16,470 B C N0RB 25,650 B B K3LL 85,337 B C AB2TC 27,786 B

THE SDR 5000 AND THE K3, HAVE ESSENTIALLY EVERYTHING A GOOD IF RADIO NEEDS.
THE TS 850S LACKS MANY OF THESE REFINEMENTS BUT IT HAS ENOUGH OF THE BASICS
TO BE A REASONABLE CHOICE ESPECIALLY FOR THOSE ON A RELATIVELY LOW BUDGET.
THESE RADIOS REPRESENT THREE QUITE DIFFERENT DESIGN APPROACHES.  THE TS
850S DESIGN IS NOW ALMOST 20 YEARS OLD USING WHAT WAS THEN A TYPICAL DOUBLE
CONVERSION IF 8R83 MHZ COUPLED WITH 455 KHZ.  WITH 8 POLE INRAD FILTERS
AVAILABLE IN USEFUL BANDWIDTHS FOR BOTH SSB AND CW, FOR BOTH IFS, THIS
RADIO CAN BE BROUGHT UP TO RELATIVELY MODERN STANDARDS.  BETTER YET AS THE
ORIGINAL REVIEW NOTES, IT HAS VERY LOW SYNTHESIZER ARTIFACTS.  SYNTHESIZER
NOISE NOT ONLY MAKES YOU A BAD NEIGHBOR BY GENERATING UNWANTED BAND NOISE
FAR FROM YOUR FREQUENCY BUT RECIPROCALLY CAUSES WEAK SIGNALS TO BE BURIED
IN THAT NOISE.  THE SDR 5000 IS WHAT I CALL A PURE SOFTWARE DEFINED RADIO
SDR.  ESSENTIALLY ALL ITS HARDWARE SERVES TO INTERFACE WITH ITS SOFTWARE
THE FLEX RADIO POWER SDR.  THIS IS A DIRECT DIGITAL SYNTHESIS DDS RADIO
‰  FROM PAGE 81  ‰
KA1CQR 12 B A N2QT 348,968 B B KB8UUZ 33,916 B B ND0C 36,698 B A KW7N 8,704
B B KB2JYZ 4 B A K4AB 268,288 B B W8KNO 26,455 B B KD0AWW 44 B A WK7P 7,112

SEVERAL OTHER FEATURES CAN BE VERY USEFUL DIRECT FREQUENCY READOUT, NON
RINGING FINITE IMPULSE RESPONSE FIR CW FILTERS, A PANADAPTOR, A REALLY GOOD
NOISE BLANKER AND THE READY ABILITY TO RUN DIGITAL MODES, PREFERABLY WITH A
1R0 PPM TCXO TEMPERATURE COMPENSATED CRYSTAL OSCILLATOR.  THE LATTER SHOULD
INCLUDE A STRAIGHTFORWARD MEANS OF CONNECTING TO A COMPUTER WITH A MINIMUM
OF ANGUISH AND HUM.  OF COURSE INTERFACES SUCH AS THOSE SOLD BY WEST
MOUNTAIN RADIO AND OTHERS ARE A GREAT HELP IN THIS RESPECT, BUT A RADIO
THAT DOES NOT NEED THEM IS EVEN BETTER.  FIR FILTERS ALLOW EXTREMELY NARROW
FILTERING WITH CONCOMITANT IMPROVEMENT IN S/N RATIO WITH NO RINGING EVEN AT
HIGH CW SPEEDS.  SINCE NOISE IS A MAJOR IMPEDIMENT IN DETECTING VERY WEAK
SIGNALS, A GOOD NOISE BLANKER CAN BE CRITICAL, PREFERABLY ONE NOT AFFECTED
BY STRONG SIGNALS ON THE BAND.  FINALLY, A GOOD PANADAPTOR DOES WONDERS FOR
TELLING YOU IF THE BAND IS OPEN AND FOR FINDING THOSE ELUSIVE CONTACTS ON
THE MICROWAVE BANDS WHERE THE OTHER GUY OFTEN HAS NO IDEA WHAT FREQUENCY HE
IS ON.  THREE IF RADIOS THE FEATURES THAT ARE PARTICULARLY USEFUL IN IF
RADIOS ARE SUMMARIZED IN TABLE 1.  AS YOU MIGHT EXPECT, THE NEWER RADIOS,
‰  FROM PAGE 81  ‰
172,874 A C N3BB 1,135,620 A C K3ZO 1,193,331 A C W4PA 931,315 A C W0EWD
582,159 A C W6AFA 49,518 B B WO4O 393,824 A C VE3OX 49,320 B B K0OU 394,790
A C N7VPN 21,887 B B WB0IWG 3,108 B A W9QL 45,420 B B KI6JJW 10,440 B B
‰  END OF 40 WPM TEXT  ‰  QST DE W1AW  ƒ