Category Archives: contests

CW contesting

If you have heard the intense activity at the CW end of the bands during contests, you might wonder how you could join in.

Assuming you have learned morse code and have used it already for ordinary contacts, how different are contests?  In some ways they are easier – no need to chat about the weather, your rig or antenna, or even your name.  To operate in almost any CW contest it is possible to figure out from listening to contacts under way what the exchange is and whether contacts are international, internal to certain countries but if you are in doubt about the rules look them up on sites such as the WIA contest page (for WIA sponsored contests within VK), or for international contests, the ARRL contest page or http://www.contesting.com/.

Once you know enough about the rules, how do you join in? Do you just call CQ TEST on an “empty” frequency? I’d suggest in most cases it is best to start out by finding someone who is either calling cq or is working a number of stations in a “run”.  In that case you will call that station using only your own callsign, sent once only.  If you get a QRZ? you either call again once, or if you think there is QRM or your signal will be weak, give your call twice. Using full break-in can be helpful because it lets you hear the other stations calling and most importantly it lets you hear your target answering another station.  You can’t do anything about that – in many contests VK is a long way from the centre of the activity so you have to put up with not being heard every time.  Particularly in Europe, but also within Asian or US contests there is a lot of QRM and a lot of very strong signals to compete with.  You have to persist and you have to be clever in your choice of frequency and your timing.

Here are some more detailed tips.

  1. Do lots of listening to contest operators to learn what is done.
  2. Initially it helps to have a pre-written sheet of standard exchanges visible so you can send from the sheet instead of trying to do it out of your head.
  3. It is usual to send only your own callsign when answering a CQ
  4. Use break-in techniques rather than “callsign de callsign” at each end of your transmission. So after receivingVk1DA 599234 599234 BK
    You reply R UR 559056 559056 BK
    the reply will be R TU and possibly a pause, in which you can reply TU
    after which the station you worked will call CQ or QRZ? and as he/she “owns” the frequency, you now QSY and look for another station to call.
  5. In a quiet or slow event there is time to send 73 and stuff but don’t bother in a dx event.
  6. If signals are strong, twice is enough for calls or numbers. Change to suit the situation. Watch for clues that you are not being copied well – the station you call gets your call wrong, or asks for repeats using AGN or just plain ?
  7. The simplest reply requesting a repeat of a number or call is NR AGN PSE  or for a callsign, QRZ?.
    For callsigns it sometimes works to send VK5? BK  but there is always someone who is not a VK5 and is convinced you want them to call again, making it tough for the real VK5 to make the contact.
  8. You need a cw filter – SSB bandwidth is too wide for a cw contest
  9. Send no faster than the station you are calling.
  10. If called by a station at a slower speed, slow down to his speed.
  11. Send no faster than the speed you can copy. (hint: practice)
  12. If you are operating at 15 wpm and callers persist in calling you at 25 or higher, use QRZ? or a CQ to convince them to remember their manners. A lot of contesters use computers or computer keyboards but this is no excuse for poor on-air procedure.
  13. Send no faster than you can send accurately
  14. You will hear stations sending callsigns at one speed but sending the exchange like 59905 or even part of it, at twice the speed.  As if that saves them any real time! The number of milliseconds saved by sending that at 40 wpm but running everything else at 25 is so small, it isn’t worth it.  I don’t recommend this practice.
  15. QRP stations and beginners at cw contesting are always better off using the “search & pounce” technique than trying to set up a run, where you sit on a frequency and have dozens or hundreds of contacts with the rest of the world calling you, unless you have outstanding signals and the right conditions.  Or unless you ARE the DX.
  16. In a pileup for a wanted station try to call on a freq between other callers. This means knowing your exact tx freq as heard by the other op. This is what a separate receiver and transmitter used to be so valuable for.  Modern rigs match your tx frequency with the sidetone so turning BK off momentarily and tapping a dit or two will let you hear your effective tx frequency.  Less modern radios have a sidetone that is nothing like the frequency offset of your radio.  You need to use a monitor receiver or another receiver and practice getting the frequency offset right.
  17. If the dx is operating split, listen for whoever he is working and what the pack is doing. If they are all on 7015.125 you need to be 200-400 hz off the pack either up or down in frequency.  This takes planning and experimentation, so you may think this will waste time, but since calling endlessly on the same frequency as 100 others won’t work at all, it is better to let a few contacts go by while you tune in to the way the wanted station is operating, where he is listening and getting your transmit frequency right before calling.
  18. Logging is usually by computer now but if you are using a key to send you will be moving your hand between keyboard and key. If logging on paper it is a smart move to learn to send with one hand and log with the other. I never learned this well enough for a contest but I still log two contacts per minute in a good contest.  Very few vk contests run at this pace for more than the first 15 minutes.
  19. Your antenna is the most important part of your station in contests.

The pc based program MorseRunner is good contest practice with some fun options. The vk contests don’t use that cipher format but it still gives you practice at copying callsigns with qrm, qrm and an occasional lid calling cw on top of your contact. All good fun. And if you google “morse runner” you find others have not only used it but added other software to interact with it.  A useful comment noted on one site: run it slightly faster than your comfortable speed. If you ever want to increase your speed you have to be scrambling, not comfortable.

No doubt this list can be expanded forever but I hope it’s of use.

QRP Hours contest – after the event

As planned I operated in this relaxed event tonight, for a couple of hours.

I decided to use my IC703, partly because it has a CW filter and I know how useful that is even in a quiet cw contest.  (I should get one for my FT817).  The other advantage the IC703 has over the FT817 is that it has a speech compressor which improves the average power output on SSB.  But as a test and a self imposed handicap I decided to cut the IC703 power level down from its nominal 10 watts to 2 watts for this event.

First an hour on CW, where I made 11 contacts.  As you can tell this is not a hard paced, highly pressured event.

Then an hour on SSB where I made 17 contacts, a few more than I did last year.  I recognised some of the callsigns from last year and also made contacts with friends such as  Mike VK2IG, Murray VK1MDP, Waldis VK1WJ and Peter Vk3YE.

I don’t think running 2 watts instead of 5 or 10 made any difference to the number of contacts made.  While 10 watts is 5 times higher, which translates to 7 decibels, 80m generally provides good propagation and there is more than enough “head room” in the available signal levels for QRP signals to be easily readable.  80m can be a noisy band on SSB especially late at night.  There was some electrical storm noise but it wasn’t too bad.  Another time those 7db might have been quite important.

A few interstate stations gave me good signal strength reports so the old 80m dipole at 6 metres above ground was doing its usual job.

The low dipole isn’t any use for dx though.  I have heard some US and JA signals on the CW end of the band but even the strong ones rarely even return a QRZ? to my call.  Have to get a decent vertical going on that band to work dx.

RD Contest – State Scoring formula

Is the RD contest state score formula correct, and is it fair?
There has been a lot of concern about the RD contest state score formula, and conjecture about how it can be improved.
I have written this to clarify my thoughts and to show others what my analysis of the scoring formula reveals.

A fundamental principle is that the scoring formula has to work in the simplest of all situations, ie. when all states have equal performance.  We know the number of licencees is different so we cannot simply add up their logs and award the contest to the state with the biggest score.  That would give the result to the largest state and that’s not fair to the smaller ones.

To analyse the situation we have to start with some assumptions.

  • Assume all operators across all states had the same average points per log
  • Assume all states had the same participation ratio, ie. logs submitted divided by licencees

Should we expect that to result in equal scores?  Seems reasonable doesn’t it?

Let’s assume each log contains 10 points  (this can be an average, if you wish) and that the participation rate in each state is 10%.
Table 1. Examples of varying state sizes and scores
State Licencees Logs Participation rate (PR) Pointsper log Score(total points*PR)
A 3000 300 10% 10 3000*10%=300
B 1000 100 10% 10 1000*10%=100
C  200 20 10% 10 200*10%=20
We find that the smaller states cannot win if all operators score the same average points per log as the larger state.  Their population is a fraction of the bigger state and they need a correspondingly higher average points per log than the larger state does.
This simple example shows that the current scoring formula does not allow for different sized states.
In most RD contests, the two larger states have had low participation rates and several mid sized states have had better rates.  To examine how those scoring rates affect the outcomes, we can insert those factors into the model and see how that affects the state scores.
We can go further and examine what a smaller state needs to do in order to score higher than a larger one.

Table 2. Further examples showing how state score is affected by participation rate (PR)

State Licencees Logs Participation rate (PR) Points per log Score(total points * PR)
A 3000 150 5% 10 3000*5%=75
B 1000 200 10% 10 1000*100/1000=100
C 200 20 10% 50 1000*10%=100

Firstly, to explain States A and B of this example, the participation rate of state A has dropped to half its level in the first table.  But note that its computed state score has cut to a quarter of its original value.  It was 300 when its participation rate was 10% but with half the particpation the final score is 75, which is one quarter of the original value.  We can observe that the state score changes in proportion to the square of the participation rate.  Hold that thought.

This change in State A’s participation has had a dramatic effect on its final score, allowing state B to score better than state A, with the same average log value as state B.

Secondly, for the much smaller state C, I have illustrated how it can achieve the same score as one that is 5 times bigger.  Its logs contain five times as many points per log as the mid level state.  Here we can observe that the state score is proportional to the average points per log for each state, provided the participation rate remains constant.

Why is the state score not proportional to the Participation Rate?

As we know the formula for state score is:

State score = PR * (total of all logs)

However the total of all logs already reflects the participation rate, as if the PR were higher or lower, the log total would be correspondingly higher or lower.  Indeed if the number of logs was halved, the total score would halve.  Putting that another way:

Total of submitted logs = Total of all possible logs from state * PR

Rewriting the state score formula, we see that the state score formula can be rewritten as:

State score = (total of all possible logs from the state) * PR^2  (ie. PR squared)

From this it is apparent that the state score is proportional to PR squared.

This is why the state score is affected so dramatically by the participation rate PR.

How can the state score formula be improved?

Clearly the formula currently does not compensate for the different sizes of each state.
Teams of differing sizes can be compared only by normalising results to the average effort of each team member.  In the case of the states competing for the RD trophy, this translates to the average number of points earned by each state licencee.
ie. Average score per licencee = (Total points on logs) divided by (total licencees in that state).
With that formula, going back to table 1 above, the average score per licencee in each state is 1.0.  The average score per licencee in the other states is also 1.0.  A tie.
And since they both produced the same average effort per licencee, a tie is exactly correct. This measure works well for the case where all states perform equally.  How does it work if some states perform differently?
Let’s recalculate table 2, where states had different participation rates and different points per log.
Table 3. Sample results with Average Score per licencee
State Licencees Logs Participation rate (PR) Points per log Average Score per licencee
A 3000 150 5% 10 0.5
B 1000 200 20% 10 2.0
C 1000 220 22% 10 2.2
D 200 20 10% 50 5.0

Outcomes:

  • The anomalous  results shown in Table 2 have gone.
  • State A: large state, low participation, logs submitted are average value, overall rating 0.5.
  • State B: medium size state with higher participation than state A, and a much higher score – 2.0.
  • State C: like state B but with 10% more logs.  Note that the score is 10% higher.
  • State D: the exaggerated example of a small state with very high average logs, scores best of all at 5.0.

As can be seen the results are linear, with increased scores resulting in a proportional increase in State score.

Where to from here?

The state score formula should be changed to the following:

State score = (total points from logs submitted) divided by (number of licencees in the state) [see note below]

I would like to see this analysis considered by contest managers and other decision makers within the WIA.  I believe that the state scoring formula was fundamentally flawed because it was based on incorrect mathematics.

It is recommended that this part of the contest rules be corrected at a suitable time, to reflect the results of this analysis. It may be too late for the rules to be changed for 2012, but perhaps this anomaly can be corrected for subsequent years.

This change would make it more feasible for the contest to be won by different states.  I believe the run of wins for VK6 has occurred due to good promotion of the contest in VK6 combined with a severe penalty for the larger states imposed by the erroneous formula discussed here.  I feel sure that with a more appropriate formula, competition would be enlivened and the contest would be a healthier and better supported event.


Note: number of licencees is adjusted to remove licencees that cannot participate in contests such as repeaters and beacons.  This is already catered for by current rules, but I did not wish to complicate the description above.

Reference:  Current rules for the RD Contest, rule 14.1 defines the state score calculation. http://www.wia.org.au/members/contests/rdcontest/documents/RDcontest2012Rules.pdf

Summer VHF/UHF field day January 2012

For this event I invited a former work colleague and new licencee, Adan VK1FJAW to participate and learn something about field operations.  Adan operated the 6 metre station during the event and while it was fairly quiet for most of the weekend, he was rewarded with a short sporadic E opening to southern VK4 during the final hour of the event.

Apart from that his role was to carry heavy stuff, help with fuel refills, put up antennas and generally be a keen student, which he did very well!

Operating from Mt Ginini was rewarding as usual.  On the bands, 2m produced a good contact score though conditions were poor in Victoria, reducing activity and stations worked somewhat.  Most of the usual Melbourne area home and portable stations were worked on 2m and 70cm, some stations in the Sydney area, north and southwards of Sydney and a few in the Port Macquarie area were also worked.

Conditions for the higher bands were not good.  Apart from local contacts on 1296, the only exotic contact was with Dale VK1DSH on 10 GHz, made possible by his trek through the bush to a more favourable ridgetop from which he heard us much better and we could also hear him.  Some odd frequency offsets were taking place but I think my handheld fm liaison rig was creating havoc in my own 2m IF rig.  We liaised via the Mt Ginini repeater – for some reason I could get into it quite well, at a distance of about 30 metres.  We had to use a combination of voice and morse to get numbers exchanged to our satisfaction.  Persistence paid off.

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QRP Hours contest 2011

This is a short contest for QRP operators.  It runs for one hour on CW mode, then 1 hour on SSB.  A truly easy contest to participate in.  All licence classes can participate as QRP (low power) or their ordinary power.  The contest was sponsored by the CW operators QRP club.

I wasn’t sure I would have an opportunity to operate in this contest but at about 6:30pm on Saturday 2nd April I decided I should put up an 80m antenna and have a go.  At 6:40 I had identified a two section telomast and was measuring out some guy ropes for it.  Having found some stakes, guying ring and found the wire antenna cross-boom with the attached halyards and pulleys, I was able to assemble the mast, attach the cross-boom, lay out the guy ropes and do a trial setup to get the guys set to the right lengths.  Once that was done I hammered in three stakes and attached the guy ropes to two of them.  Walking the mast up to vertical showed I had set one guy at an impossibly long length so it all had to come down.  Next time was ok so I could walk the third guy out to the stake and tie it off.  One 20 ft feedpoint suspender ready for action. Time about 7:15.

I had a 80/40m dipole assembly last used two years ago at a rental property in Canberra.  I attached the centre conductor to one of the halyards and hauled it up to the dizzy 20ft height of the mast.  Then I attached some light cords to the antenna ends and tied it to the fence at one end, and to some ground stakes at the other end of both dipole wires.  This work was completed in the dark as the sun set at about 6pm local time.

The two dipoles are joined at the centre.  This works because the 80m antenna is a very high impedance on 40m, so is virtually “not there at all”. The 40m dipole detunes the 80m one slightly but I went through the adjustment process with this antenna about 20 years ago and have simply rolled it up when I finished using it each time.

Then I got out the FT817 and found a suitable keyer cable, microphone, power supply.  On 80m the dipole presented a 1:1 match on the CW end of the band so that was fine.  On 3690 it was about 1.3 but my Emtron tuner handled that mismatch with a fairly broad dip.  The time now was about 19:45 local and the contest started in 15 minutes, or so I thought.

At 20:00 local time I heard a station calling CQ TEST so I answered, received a number, gave a number, signed off.  Good start to the contest, I thought. Then I called CQ TEST myself.  No replies.  Tuning around showed nil activity.  Called CQ again.  This time I got a reply from an operator who kindly advised me that the contest was not due to start until 2100 local time.  I opened up the computer and checked the contest rules.  Start time 1000 UTC, which was 9pm local, but somehow I had reverted to non DST in my calculations due to daylight saving ending later that night.  1000 UTC was almost an hour away.  So I had time for some dinner!

About 45 minutes later I went back to the radio and started the contest again at the right time.  Signals were strong and most stations were in the vk2, 3 and 4 areas though there were some vk5, vk7 and ZL stations worked too at signal reports of 559 or so.  I made 10 cw contacts in this hour.  A slow contest compared with the DX contests but it was also quite relaxed and unrushed.

At 1100 UTC the SSB section commenced, operating between 3550 and 3590. Signals were very strong from some stations.  Again a few names were exchanged as well as the contest numbers.  15 contacts on SSB, and I got the impression the antenna was working well, as mostly my replies were answered after only one call.  Quite good for a 5 watt signal.

I have sent in my log and I don’t think this is the only QRP event I will operate in.  This was a very enjoyable process and quite rewarding for the minimal effort required to get on the air.  Next time: antenna up another 10 feet.  And the ends should be higher too!  Should be no problem.  I might even do most of the work in the daylight next time.

Mast and 80/40m dipoles
Mast and 80/40m dipoles
Feedpoint of 80/40m dipole
Feedpoint of 80/40m dipole

National Field Day contest March 2011

Antennas for 144, 432 and 1296

I plan to operate in this event from home, starting on Saturday evening due to a family commitment that afternoon. I will operate on 144, 432 and 1296 MHz bands only, unless I am inspired to erect more antennas.

Post contest note: I made 40 contacts in the few hours I was able to operate on 144, 432 and 1296.  Only a couple of contacts on 1296 but one was to VK2BPK a club station operating from a hill just north of Grenfell.  I think that’s the site of the Grenfell 2m repeater.  133km from my location at Yass.

In completing the log and looking at the scoring I noted that the scoring for home stations does not appear to give any incentive for home stations to make contacts with the more distant field stations.  The 2 points I get for working a local station on 2m is the same as I earn for  a 505 km contact with VK3UHF near Geelong, a much more difficult contact.  The purpose of increased points for more difficult contacts is to encourage people to improve their stations and in this kind of contest it encourages home stations to make contacts with distant field stations.  There is a full table of scores earned by field stations for different distances.  However much the field station may wish to make long distance, difficult contacts, the home stations have no incentive other than their own interest in such contacts.  An odd aspect of the rules.