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

3

VHFers like to work grid squares

World is marked off into 1 x 2 degree rectangles called grids

New Mexicohas 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

In Motion 2008 CQ WW VHF ContestAdvantagesMore operating timeLess set up timeDon’t miss openingsDisadvantagesSub optimal signalsAntenna limited

Stop and Set up June ARRL VHF 2008AdvantagesGood locations, high, low noiseLarge antennas possibleDisadvantagesset up timetravel time

Operate in Motion? or Stop and Set up?

7

Different Station Each Contest

8

Rigs

June 2008 ARRL VHF ContestSIx Meters 80 WattsIC551DTwo Meters 125 WattsTR-9130TE Systems 1512 amplifier70 cm 10 WattsFT780R

Things tidied up a bit for August 2008 UHF70 cm 50 wattsFT780RMirage (KLM era) 3010 amplifierTwo meters for liaison

9

The Back side isn’t so pretty

10

Antennas - Stop and setup

Six meters2 element Yagi W6MMA SuperYagiTwo meters 6 element WA5VJB Cheap and Easy Yagi13 element Cushcraft 13B270 cm11 element WA5VJB Cheap and Easy Yagi

11

Antennas - Operate in Motion

Six meter Square half wave loop (homebrew)Two meter 3 element WA5VJB Cheap Yagi70 cm Symmetrical Double Rectangular loop (Skeleton slot)

12

Mast Mounts

Homebrew drive on mount NN5K receiver hitch mount

13

How the antennas go up......

Traveling position, antennas stowed on roof rack and mast lowered

14

Six meter elements slide into boom......

15

Install 70 cm beam.....

16

Straighten Out 2 Meter Elements...

17

Install 2 Meter Yagi...

18

Connect Feed Line.....

19

Make sure antennas are all pointed in same direction...

20

Make sure feedline is connected...

21

Raise Mast and We’re on the Air

22

Normal Operating Position...

23

At night...

24

Getting Coax into the Car

Use foam pipe insulation on top of window before it is rolled up

25

Power Plug(cigar lighter)

Battery ChargerDC/DC Converter

70 AHDeep CycleBattery

N8XJKBatteryBooster

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

26

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

27

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

28

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 capability

29

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

30

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

31

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

32

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

33

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 January33

34

Official KK6MC/r Driver and Photographer