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December Foxhunt 2025

The December hunts tends to be a bit unusual, deliberately planned for a short night. It’s a good opportunity to try some novel ideas.
This time, the CI team had a street orienteering map with many good fox hidey holes all in the one area, so instead of drip feeding the hunts out over years, we decided to put all the foxes out at once. What started out as a 5 TX concept grew out to the standard 10 frequencies, to add more choices, tradeoffs & hard decisions to make. Strategy!

There were 10 transmitters, all on the Mt Gambier mode frequencies, for ease of sniffing.
However, the hunt differed somewhat from the Mt Gambier sniffer hunt:

  • The TXs were were different point values, ranging from 1-7 points
  • A combination of car and running were envisaged to get the best result
  • Points were set not only on distance from the start, but difficulty in getting to the TX. The two highest scoring 7 pointers were relatively close to the start.
  • Scoring based on a Score event format with a 1 hour time limit (with late penalties). Order into a TX was irrelevant.

Teams took varying strategies to cope with all this information. Just getting the maximum number of TXs did not guarantee the best score; in fact, prior to late penalties, the best scoring team, FOX, only found 5 TXs but with 23pts. FAST found 6, but scored 21. However, FOX would have been better giving up after only 4 TXs, scoring 19 pts, instead of a whopping 7 pt late penalty hit, moving them from 2nd to 3rd on 16pts. MD only found 3, but remarkably ended up in 2nd with 18 pts, only 28s late (1 pt off). OW threw away more than half of their points in penalties. Despite being accused of “sending them out again”, the fox did no such thing, only telling them they were 10mins early; did they want to finish early?. The decision to head out again was theirs entirely!

TeamTX #s foundScoreScore with lateFox Score
FAST2,5,7,8,9,10212119
MD4,5,6191822
FOX2,3,5,7,8231624
OW2,9,109436

Here’s the Fox-eyes-only map (you can figure out TX# from frequency noted):

Can you spot the error?

E was further in along the creek.

The only TX not found by any team was H on 144.000 (#1) . I could hear it from the start, so it was certainly running, but with only 2pts maybe wasn’t worth the effort.

Since the TXs are all programmed up this way, the ARDF Christmas hunt might be a smaller, on-foot variant on the same theme. Perhaps with an extra twist?

Hunt 2

Hunt 2 was are more traditional two legged vehicle based hunt. OW and FAST decided to not trouble the 1st leg fox, and in fact OW elected to not get in on either leg, preferring instead the other side of the creek. We had to start the two missing teams 2nd leg times based on when the 1st fox was turned off. This could give them up to a couple of minutes advantage on the 2nd leg, depending on where they are located at the time, but missing the 1st leg is hardly a winning strategy!

FOX won both legs convincingly.

Supper Hunt

Park not far from the Supper location, carefully set to encourage teams to entert supper from the correct entrance. All teams found this fox, with FAST taking the honours, with MD right after.

Many thanks to Olga for laying on the banquet supper.

Scores

Hunt/TeamFOXOWFASTMD
124361922
2A010106
2B01059
Supper5801
Final Score29643438
Place1423
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SERG Homebrew entry 2025

I was little bemused at the summary given of my homebrew entry this year. It was for a semi-automated tester for our foxhunt systems, and we actually did end up using it quite a few times over the Mt Gambier foxhunting weekend, amongst our multiple gear failures.

The description given of the tester itself was fine, but the SDR timing problem that prompted the tester in the first place was a bit misrepresented.

The issue had nothing to do with SDR software ‘not keeping up’ due to lack of PC resources, but more the discovery that the particular SDR software I was using, GQRX, has what can best be described as an underlying design flaw, rather than a software bug.

It’s a bit of task to re-write GQRX to remove the fault, so at present I get around the problem by effectively automatically restarting the SDR periodically; whenever the fox channel is changed, or every 10 minutes, before any time delays can manifest significantly.

As our SDR rotating system was only available less than half the time, due mainly to water ingress problems, I can’t say for sure, but I believe we didn’t experience any more timing problems.

Here is the Homebrew entry documentation. Of particular interest may be the story of the hunt for the timing issues in Appendix 1.

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Report on Radio Combo Event 7 May 2022

A Radio “Combo” event was run in conjunction with the Saturday afternoon Orienteering event at Endeavour Greens on 7 May 2022. Unforunately the weather was rather poor but despite that we had eight people competing.

Five 2m Fox-Or transmitters were placed in bush or park areas on the map and competitors had to locate these once they had reached the large red circles on the map. A copy of the map is below with small blue dots indicating approximate transmitter locations. A 75-minute time limit was set with 3 points per minute late penalty. The event was run using MapRun and no flags were set with the Fox-Ors.

Congratulations to Bruce Paterson who got all 20 orienteering controls and 5 Fox-Ors in the time, achieving a perfect score of 120 points. Newcomer Christopher Hall also did very well, getting all five Fox-Ors and all but three of the orienteering controls. Chris also managed his time very well, returning 30 seconds before the 75-minute deadline. Monica Lo Presti came in third with a respectable 91 points. Jack Bramham was feeling a bit unwell following a flu vaccination the previous day but still went out to get one of the radio controls after spending some time getting MapRun set up on a new phone. Scores are copied below (also available on MapRun “Leader Board”):

Results

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Hays Paddock Sprint ARDF Training

Hays Paddock training event is on from 9 Oct – 24 Oct (or later if requested). For now only if it’s in your 15km circle, but fingers crossed that may change, before the batteries die.

Sorry if outside your circle – I tried to suit as many as I could !

The 2m transmitters are on daily from3-7pm daily. Time limit 90 minutes. Frequency 145.300 MHz, 5TX Sprint Mode

The event will be on MapRun6. Use the QR code on the map, “Events Near Me”, or in Victoria/OV-Clubs/AmateurRadioDirectionFinding-ARDF/

The start, as shown on the map, is the northern track junction east of the carpark.

Here’s the map:

hays_paddock1Download

So that’s a wrap.
Tracks and results are now visible here

Congratulations to Jack on the winning time, and I think a pretty impressive track. Apologies to those who missed out on hunting down #3, when it had a temporary outage. I can see some spent a while on long excursions looking for a signal. Click on any of the tracks to see where it actually was located. Jenelle just beat out hubby, leading a large cohort who were all close after the 50min mark. And well done to Peter M who, as usual, did the event in PMT as the controls were being picked up. He brought the total up to 16 competitors, which is a great effort.

By the way, #5 was located on the peninsular south of the creek (which is even more ‘loopy’ than mapped), but seems MapRun just allowed check-ins on the north bank, as I can see a few made use of! Oh well. We awarded Greg #4, as he was unable to get there due to the lake flooding.

Many thanks to Bill, who was able to monitor the TXs for me when required, and who we can all thank for restoring #3 to health – three times! (all for differing reasons). The firmware will upgraded so the website auto-update can be stopped for easier/safer delayed-turn-on programming (reason 1). #3 will receive a new battery (reason 2 & 3).

PS: The next version of MapRun6 will have configurable control punch tones, which will be much more satisfactory for handsfree (phone in pocket) ARDFing.