Building a Contest Station and getting seduced into SO2R A personal reflection
Three parts to my talk The basics of contesting The G5W story SO2R and putting it all together
Why Contests? The arguments
Why Contests? A never-ending challenge - doing better each year Choose your category and your peer group Work out how you can improve after each event Contesting makes your station better and you a better operator Great camaraderie
Planning to operate contests? How ambitious should I be? Which category should I enter? What is my competition? What hours can I do? What commitment casual or serious? Be realistic
The elements of a contest station Transceiver(s) Software Control system(s) Antennas Filters Internet support The investment you have to make depends on your chosen category
Transceivers for Contests Key criteria: Listening fatigue Strong signal performance ip3 Cool running Selectivity and DSP Transmit wideband noise Ergonomics Reliability No transceiver is top in all the above compromise is necessary
Transceivers for Contests (2) Top of the range transceivers Hilberling, FT5000, K3, TS590, Flex 5000 (SDR) But perfectly good possibilities with cheaper, smaller and older equipment Transmit audio is critical Heil microphones and (in modern rigs) proper equalisation Transmit phase noise important in SO2R single band
Software for Contests In early 2000 s G5W evaluated Write-Log, WinTest, SD and N1MM SD otherwise suitable but did not network for multi-station use Writelog networking too fussy Win-Test selected because of bomb-proof networking and resilience Until now, it has proved the test of time but N1MM+???
Control systems for contests Advisable: Automatic antenna selection, voice keyer, CW keyer, point and shoot rotator (or computer tracked), SteppIR band-tracking (if using SteppIR) Essential (for SO2R): SO2R Controller bought or home-made (easy)
Antennas for Contests If an antenna stays up for a year, it isn t high enough Wrong! The big contests tend to take place at the equinox, as do the high winds. Reliability is better than the extra 0.2 db! Put them up to stay up.
Antennas for Contests Choose your category. From single element to multi-element Single band or multi-band? Avoid traps - lossy Vertical vs horizontal? Beam vs omni-directional? 4-sq vs yagi? Broadband? Winning antennas can cost just a few
Antenna switching for contests Should be automatic for multi-band station - from computer or decoded from band data Put switch box at remote end of feeder, to minimise # of coax-runs Buy remote switch, or build with open-frame or high power sealed relays & ip65 box. Various PC boards available KK1L, SJ2W, UTP for control lines (but beware furry creatures)
Filters for contests Band-pass needed in multi-transmitter environment Several sources for BP filters build or buy: W3NQN (Array Solutions) Dunestar (Dunestar Systems) 5B4AGN 4O3A Best to auto-switch them computer or external decoding of band data. May also need co-ax stubs
Internet Support Move towards allowing cluster/rbn support in all categories of entry Use logging band map set persistence and bandwidth carefully to avoid overwriting legacy data Choose what to display on band map mults or all On CW use RBN as well VE7CC is a good cluster node BUT don t rely on cluster find additional multipliers yourself
About me & G5W - and our journey in contesting
A little about me First licensed 1961-160m and 2m AM/CW SSB in 1965 First tower 1969 + trapped tri-bander Progressive enhancement, but work pressures Serious contesting from the late 80 s Now G5W is regularly top in the UK (and quite good in the world) in major contests A preference for CW
Life in a medium plot Buckinghamshire village 1973-2001 120ft back garden and 60ft front Tower near house supported LF dipoles and tri-bander 80/40 vertical at bottom of garden and vertical fan dipole for 10-20 led to first steps in SO2R
Life in a medium plot (2) EMC challenges Noise quite low but increasing No room for receive antennas But good results got into the serious results league Early days for SO2R, but multi-single in contests
Building G5W in Shropshire Retirement in 2000 and a house move to the real country Careful choice of house: space for antennas, no immediate neighbours, good take-off, no power lines 14 years later it is still a low-noise location, but the trees are higher!
The progression at G5W Initially one tower (10-40 yagi), and dipoles. OK for single operator contests, but I began to lose out to SO2R-enabled stations Added second tower for a second set of HF antennas, and 90ft Titanex vertical for LF Added K9AY steerable loop and beverages for receive Second rig and linear with control circuitry can be used in SO2R or multi-single configuration
SO2R Single operator, two radio
What is SO2R? Single operator, two-radio A capability in an amateur contest station that allows one operator to maximise band coverage and QSO rate by working two bands at once. SO2R involves listening on one band whilst transmitting on a second.
SO2R why? In contests, there are many trade-offs band, beam heading, running or search & pounce SO2R reduces the number of choices, and so improves the rate Enables search for multipliers whilst running on another band Allows propagation on other bands to be checked whilst running elsewhere
Contests suitable for SO2R Multiband contests (single band only possible with big antenna spacing and good equipment*) Especially where multipliers count once per band Lower rate contests Where it is necessary to move stations through the bands *especially transmitter phase noise
How does it work? Band 1 CQ Listen for replies Send exchange Receive exchange Acknowledge and QRZ Band 2 Search for mults (Search for mults)* Search for mults (Search for mults)* Search for mults * Advanced
How does it work (2)? CQ duelling Band 1 CQ Search for reply band 1 CQ Search for reply band 1 CQ Search for reply band 1 Band 2 Search for freq band 2 CQ Search for reply band 2 CQ Search for reply band 2 CQ
Requirements for SO2R Two complete stations with no interaction between them Appropriate SO2R controller can be very simple Good software most leading contest loggers support SO2R Good ergonomics and total automation Most importantly - good operator!
SO2R is for the big guns No! This presentation includes a full implementation of SO2R, but don t forget it works for more modest stations It may be even more relevant to (and easier for) lower power, modest antenna stations
An SO2R station Tx/Rx BPF auto Linear (auto?) Antenna auto Control of keying, PTT,and audio routing Paddle Microphone SO2R Controller Headphones Control of keying, PTT,and audio routing Tx/Rx BPF auto Linear (auto?) Antenna auto Note: 1: Auto = tracks the transceiver band 2: Computer interfaces not shown
Why auto-switched? Tiredness = errors A momentary lapse of concentration and the BP filter can be blown, or an antenna balun destroyed Band-switching to chase mults made easier if amplifiers are auto-tune
Transceiver requirements No specific requirements other than good contest radio, ideally with second receiver Needs to have CAT If wide antenna spacing is possible, good transmitter phase noise performance is essential to be able to do in-band SO2R
Linear requirements Ideally auto-tune (but not essential) Quiet (there will be two running ) Does not trip when a second strong signal is close by (or else stubs will be needed). Some solid state amplifiers can be touchy here
Antennas One good antenna per band is the ideal Alternatively, two tri-band yagis, and one antenna per band for LF Even just two multi-band verticals to start with well spaced Care needed to handle antenna switching home built box or commercial unit (e.g. Array Solutions six-pack) Above all, think about the combination of antennas that you will need (and can implement) and how you want them switched
Receive antennas Care needed, as there will be another transmitter on-air whilst using the receive antenna(s) Must be able to receive when other station is transmitting. Ideally either wide separation, or switched BPF on the receive antennas. If close spaced, protection of active components in rx antenna (and transceiver) may be needed simple relay box
SO2R at G5W SO2R in practice
G3BJ/G5W antenna solution Two Heliax feeders to the antenna area of the garden (150m) Two complete sets of antennas, one on each feeder, remotely selected Band data, from both FT5000s, drives selection of Dunestar BP filters and antenna A/B switch allows reversal of antenna banks between the transceivers (band data moves at the same time) Home-brew antenna switches (in hermetically sealed boxes); UTP control lines Repeaters for rotators because of distance
G3BJ Antennas Bank A Bank B SteppIR (10-20) @ 10-40m yagi @ 85ft 60ft 80m dipole Titanex V160HD (40160m dipole 160) 90ft vertical A3S set @ 100 Butternut HF6V* degrees* Bank A and bank B fed one to each transceiver can be reversed * For that quick multiplier when the beams are all wrong K9AY and beverage receive antennas to each transceiver, band-pass filtered
SO2R Controller Home-brew or commercial Needs at a minimum to handle A/B switching linked to logging programme, and audio routing. Building-in Win-Key and DVK is also helpful (but not essential) Simple home-brew design available Commercial products include Micro-Ham u2r or MK2+ and EZMaster (no longer made, but ebay)
G3BJ SO2R Controller
Microham μ2r
Microham Mk2R+
YCCC SO2R box http://www.k1xm.org/so2r/
Software for SO2R Must cater for two-radio operation Win-Test, N1MM and Writelog all do this Must interface with SO2R controller: Most handle MicroHam, Wintest handles EZMaster as well. Advanced audio switching must be part of the logging programme If home brew controller, assertion of LPT pins 14 (rig select), 16 (PTT) and 1/17 (CW) essential unless USB or firmware-based
Picture of logging screen - WT
Putting it together SO2R in a nutshell
Putting it all together Check out all interactions Are you locked out to prevent same-band transmit? For difficult interactions, use λ/4 open stubs (not with multiband antennas) Once the hardware is set up, configure and get used to the software switching between radios Configure all CW messages don t worry at this stage about run and S&P differences Configure DVK messages
Typical initial CW messages F1: test C/S C/S test F2: 5nn SER F3 tu C/s test F4 C/S F5: logged call F6: nr? F7:? Insert: logged call + f2 +: c/r + f3
Practical hints Never use the paddle on CW except in extremis! Always use auto-cq keep a rhythm going Logging programme will give you sidetone when you use paddle Use headphone latch mode to start with - don t use audio blend until you are happy with the basic SO2R operation Have a good ergonomic layout of equipment Beware delayed logging
Getting proficient? Introduce audio blend (including Win-Test advanced features) Move to SO3V! CQ on Rig 1/VFO1, mult hunting on Rig 2, working and mult hunting on Rig 1 VFOs 1 & 2 Alternate CQ (when business is slow)
A few details of the G3BJ/G5W station
The current station configuration RX antenna feed FT5000 BPF Yaesu VL1000 RX antenna controller & pre-amps/ filters Beverages K9AY Antenna switch Decoder controller C/o switch Microham μ2r FT5000 BPF Antenna switch Acom 2000A Dipoles Signal path Control line
G3BJ - today
Rx antenna controller Antenna /filter decoder/controller
G3BJ Titanex Photo 1
Photo 2 G3BJ Main Yagi Second Yagi
K9AY receive antenna (wires enhanced)
Third Yagi fixed
Further developments SDR on antenna for CW contests Fun Cube Dongle Pro+ for in-band multiplier hunting in single-operator (no cluster) contests In-band SO2R need a second K3! Pre-amp on receive antennas to balance levels between main and rx antennas (no need to switch FT5k preamp)
How to parallel feed an SDR eg FT5000 RX ant IN RX ant OUT Switch if need to use RX antenna RX ant feed BNC tee-piece USB to computer SDR
Conclusions Contest are fun! From 90 minutes to 48 hours Choosing your category is important Gain experience and then raise your sights Always write yourself a report after a contest of the good and bad points for next time SO2R helps if you can do it
Conclusions SO2R is a demanding style of operating but it can make the head hurt Its success is partly about the hardware and software, but mainly about the operator Don t expect to construct an SO2R station and immediately achieve results. Sorting the technology can be quite quick, but selftraining takes time! Overall SO2R is a challenge mastering it is very satisfying
Questions?