1 / 20

VHF Contesting Primer

VHF Contesting Primer. PVRC Contesting Seminar Fredericksburg, VA W3ZZ – 3/19-20/2005. LOCATION. Clear in directions of high activity Space Wave – EPA, NJ, NY, New England Es - 180 °-300° Above the trees No Noise Pollution Alternative locations Portable Hilltops Rovers.

linh
Download Presentation

VHF Contesting Primer

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. VHF Contesting Primer PVRC Contesting Seminar Fredericksburg, VA W3ZZ – 3/19-20/2005

  2. LOCATION • Clear in directions of high activity • Space Wave – EPA, NJ, NY, New England • Es - 180°-300° • Above the trees • No Noise Pollution • Alternative locations • Portable Hilltops • Rovers

  3. STATION DESIGNOverall • Multimode Radios • HF+V/UHF Radios • Multiple Transverters • Microwaves

  4. STATION DESIGNReceivers I • Huge Signal Disparities • Weak Signals • Relative lack of QRM

  5. STATION DESIGNReceivers II • Adequate sensitivity • Superior strong signal handling capability • Low phase noise

  6. STATION DESIGN Transmitters I • Enough ERP to be heard • Few pileups • Amplifiers >200 watts expensive and difficult to find

  7. STATION DESIGN Transmitters II • 100-200 watts • Home brew amplifiers for powers >500w

  8. STATION DESIGN Antenna Systems I • Single band • Very sharp patterns with few sidelobes • Usually more gain than HF • Ground gain unimportant except on 6m • Many λ high • Low loss feedline critical

  9. STATION DESIGN Antenna Systems II • Modern electrical design • Reasonable mechanical design • Reasonable size • At least Belden 9913F7 or LMR 400UF • Multiband stacks

  10. INTEGRATION BOXES • Instant band changing • Transverter selection • Amplifier switching • Audio distribution • CW keyline distribution • Microphone distribution • Digital signal generation [WSJT] • Remote preamp sequencers

  11. OPERATING BASICS I • Major and minor VHF contests • ARRL January Sweepstakes • ARRL June/September QSO Parties • CQ WW July VHF Contest • ARRL August UHF Contest • ARRL 10 GHZ Contest • ARRL and DUBUS EME Contests • Spring/Fall Sprints

  12. Bands Scoring Q points – band dependent X Multipliers – sum of grid squares per band OPERATING BASICS II

  13. OPERATING BASICS III • Operating frequencies

  14. OPERATING BASICS IV • Propagation • 6 meters • 2m, 1¼ m, 70 cm • Microwaves • Common/enhanced distances • Propagation modes

  15. OPERATING BASICS V • Zero sum game • Moving band to band • Calling CQ vs S&P • Other guy’s environment • Band “openings” • No activity between midnight and 7 a.m. • Be aware of local rover routes and times

  16. SERIOUS VHF CONTESTING • Level of competition is reasonable -Current winners the equivalent of HF little pistols • Physical location is the key • High, clear and quiet • Massive microwave station is required • A matter of integration – pieces are available commercially • Accurate pointing – digital readout • Cost is reasonable compared to high level HF contesting if you can do your own antenna work

  17. SERIOUS RADIOS • Two identical HF IF strips • Orion, FT1000MP/INRAD, Elecraft K2 • FT9000, IC7800 • One 2 meter/70 cm microwave IF • See above – or SDR1000 • Transverters for 6m through 3 cm • DEM, SSB, DB6NT • Amplifiers for 6m through 3 cm • Lunar Link, DEM, DB6NT, surplus

  18. SERIOUS ANTENNAS • TOWER 1 86 ft • 6M 6xC5-50 [C3I] @ 30, 44, 58, 72, 86, 100’ 17.8 dBi gain • TOWER 2 100 ft • 2M 6xFO12 [C3I] @ 52, 64, 76, 88, 100, 112’ 22.5 dBi gain • TOWER 3 80 ft • 1¼M 2xFO16/70cm 2xFO22 [C3I] [H frame] 19.1/20.9 dBi; 33cm 2x3333LY/23 cm 2x2445LY [Directive Systems] [H frame] 23/24 dBi • TOWER 4 60 ft • 13/9 cm 6’ dish dual band feed 31/34 dBi; 5/3 cm 4’ dish dual band feed 35/40 dBi

  19. THE BOTTOM LINE • Interesting propagation • Technical challenges • Really weak signals H a v e F U N !!

More Related