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Roving in VHF Contests. Presented at the 2009 HamCon ARRL Rocky Mountain Division Convention May 30, 2009 KK6MC James Duffey. 1. What Is a Rover?. Competitive Class in VHF/UHF Contests Goes from grid square to grid square operating from each
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Roving in VHF Contests Presented at the 2009 HamCon ARRL Rocky Mountain Division Convention May 30, 2009 KK6MC James Duffey 1
What Is a Rover? • Competitive Class in VHF/UHF Contests • Goes from grid square to grid square operating from each • Can work the same station from different grid squares • Additional multiplier for operating from grid
VHFers like to work grid squares World is marked off into 1 x 2 degree rectangles called grids New Mexico has 22 grid squares
Why Rove? • Provide more contacts and multipliers for other contestants • Produce more multipliers for self • Work more stations – dupes reset to zero at each new grid! • Operate from other than home QTH • Lower noise • Better location • Rare grids • Go where activity is • Challenging operating and technical conditions • See new sights
The Challenges of Roving • Setting up effective multiple band VHF/UHF contest station in a vehicle • Power • Antenna • Operating position • Set up new station for each new contest • Planning • Best route to get from one site to another • Best sites for operating • Good radio horizons • Easy access • Proximity to other ops
Operate in Motion? or Stop and Set up? In Motion 2008 CQ WW VHF Contest Advantages More operating time Less set up time Don’t miss openings Disadvantages Sub optimal signals Antenna limited Stop and Set up June ARRL VHF 2008 Advantages Good locations, high, low noise Large antennas possible Disadvantages set up time travel time
Different Station Each Contest
Rigs June 2008 ARRL VHF Contest SIx Meters 80 Watts IC551D Two Meters 125 Watts TR-9130 TE Systems 1512 amplifier 70 cm 10 Watts FT780R Things tidied up a bit for August 2008 UHF 70 cm 50 watts FT780R Mirage (KLM era) 3010 amplifier Two meters for liaison
Antennas - Stop and setup Six meters 2 element Yagi W6MMA SuperYagi Two meters 6 element WA5VJB Cheap and Easy Yagi 13 element Cushcraft 13B2 70 cm 11 element WA5VJB Cheap and Easy Yagi
Antennas - Operate in Motion Six meter Square half wave loop (homebrew) Two meter 3 element WA5VJB Cheap Yagi 70 cm Symmetrical Double Rectangular loop (Skeleton slot)
Mast Mounts Homebrew drive on mount NN5K receiver hitch mount
How the antennas go up...... Traveling position, antennas stowed on roof rack and mast lowered
Getting Coax into the Car Use foam pipe insulation on top of window before it is rolled up
N8XJK Battery Booster 70 AH Deep Cycle Battery Power Plug (cigar lighter) Battery Charger DC/DC Converter Rigs & Peripherals Handling Power • - Charges battery while engine is running • - Isolates battery from car electrical bus • - Provides 13.8 V until battery is discharged • - Rigs operate at optimum voltage without degradation • - No permanent connection to car • - Battery can operate rigs all day without charging • - SSB and CW are pretty low duty cycle modes, even • - Charges battery while engine is running • - Remove and charge battery at night
Trip Planning - Maps • Road Atlas with lat and lon (Rand McNally, Universal, some National Geographic) • Benchmark Atlas for detail (also DeLorme) • Google Maps • F6 Gridmap overlay for Google Map • Google Earth • World Wind (NASA - one stop shopping) • Topo! (National Geographic) • On line topo maps, Topozone, other • Printed maps from the internet usually have poorer resolution than the paper equivalents 26
Trip Planning - Other • 511 Road conditions and construction information • Motel reservations - it is amazing how much can go on in a small town in one weekend • Ask veteran VHF contesters for good rover and operating site information • Get permission where necessary • Publicize it on internet • I keep e-mail list and announce trips
Planning - Path loss capability path loss capability (plc) = efffective isotropic radiated power (eirp) + effective receiver sensitivity (ers) eirp = (10*log(P)) + Gtrans - transTL where P = transmitter power, Gtrans is gain of antenna, trasnTL is transmission line loss ers = -10*log(k*T*B) + Grecv - recvTL - threshold where kTB = receiver noise power in bandwidth B, Grecv receiver antenna gain, recvTL receiver transmission line loss predicted snr = plc - pl For my 25 watts to the WA5VJB Yagi: P=25W, Gtrans=10, transTL=1 eirp:23 dBW For a modest 2M weak signal station: T= 438 K (equivalent to nf=4dB), B=2500 (SSB), Grecv=15dBi, recvTL=1, threshold=0 (SSB), ers:-182 -- and the effective path loss capability plc: 205 dB
Planning - Path Loss - Path profile and calculated path loss from on line SPLAT! (W5GFE) - Path loss is for 50% reliability; 50% of the time it will be worse, and 50% of the time it will be better - Prediction is for ~200 dB path loss - Made QSO on second (or more?) attempt an hour apart - Online SPLAT! has holes in coverage and occasionally does strange things
Rover Strategy • Start at grid convergence or grid boundry near populated area • this lets people know you are on and gets their attention • gives them two quick multipliers • Keep moving and keep operating • more grids are more multipliers • maximize operating time while maximizing the number of grids you go to • Be loud on two - beam and amp • Publicize where you are going and when • Always sign/r, always use phonetics, always give grid when you call CQ • Have CW available 30
Tips for Fixed Stations to Work Rovers • Know who is going out, where they are going and when they will be in what grid • Keep track of the rover’s progress and location during contest • Swing the beam • Ask if they have additional bands • Ask where they are going next • Listen for the weak ones • Have CW available 31
Setting Goals in Contests • “Goals keep one focused, driven, and effectively measure one’s progress.” - AA5B • “... there is no harm in charging oneself up with delusions between moments of valid inspiration.” - Steve Martin (“Born Standing Up”) • Goals set for June 2007 VHF Contest (first rove) • 100 contacts (how hard can that be with E on 6?) • call in QST results (top in division or top 5 in region) • Long term goal set before September 2007 VHF Contest • rove from all 22 grids in NM • Met in September 2008 VHF contest • Long term goal - reverse VUCC • Long term goal - improve rover each contest
Status of KK6MC/Rover • New TS-2000X reduces clutter and adds a new band 1296 MHz, fixes 6M problems • 222 MHz up and running at 120 Watts with 6 element WA5VJB • Move up from Limited Rover to Classic Rover Category • Future plans • laptop logging • 10 to 12 ft boom Yagis on 2M and 70cm • WSJT • Will be going to northern AZ in June • Colorado in July, September, or January 33