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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.