Mt Noorat VK3/VS-054 no-show Sunday 0800Z due to BS170 PA FET #fail

My spots around sunset last Sunday from Mt Noorat VK3/VS-054, 1 point, north of Terang, Western Victoria, resulted in zero chasers. I knew something was wrong as I’ve been in this situation before. Sure enough, I had blown my output FETs in my homebrew CW rig. These rigs have no niceties like overcurrent or SWR protection. Most likely I transmitted into the 20m antenna on 40, or vice versa.

Only 24 hours before I had a ripper of an activation at Mt Leura (also 1 point), when I worked seven VK ZL chasers on 40, then 11 Eu and US chasers on 20m, all on the same rig and antenna.

I travel minimal and light and have no means of RF detection. After calling CQ on 40 and 20 for 10 minutes with not a squeak of interest, I started thinking my transmitter had turned into an elaborate CW practice oscillator and I could have been doing this on the bench at home.

David VK3KR monitored VK5ARG KiwiSDR and reported not a trace, a sure sign that no RF was emanating. Under current conditions and at that time, 20mW would have been heard on that receiver.

So apologies for wasting anyone’s time, particulalry anyone who I worked 24 hours earlier from Mt Leura VK3/VS-050.

For the VKs, Mt Noorat is well worth a visit even if you don’t take radio. Like some of the other western summits, the peak is on the rim of a volcano, providing a pleasant walk from the carpark, all-round views of the rich and fertile Western plains. The mouth of the volcano is perfectly preserved, and forms a shallow parabolic dome, quite remarkable.

73 Paul VK3HN.


At least you had some great views Paul ! Sorry to hear about the finals.
Glenn VK3YY.

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Hello Paul,

I had a great pleasure hearing your DX QSO on your Saturday activation.
Now it’s a bit sad to know you had some dead rig on Sunday, but I’m sure you’ll soon replace your blown finals in your nice tiny homebrewed rig.

Perhaps it does worth to pair your TRX along with an SWR indicator, some sort of SWR bridge or any other of the existing solutions, like this one that probably fits in your pocket size rig:

Some interesting discussion here:

Another interesting kit is here:

As discussed here:

Now you’ve got lots of literature to digest!

Take care and wishing to have a new QSO with you soon Paul!

73 Ignacio


Thanks Ignatio.

The links to lightweight and compact SWR indicators will be interesting to read, it wouldnt take much to add a basic RF sensor to my minimal portable station – it could be built into a coax adapter or lead, a small coupling capacitor, diode rectifier and a LED might be sufficient to at least indicate power.

An SWR RF sampling transformer could provide a LED indicator of SWR which would be better. Simple accessories for RF power and bettery monitoring are fun projects taht don’t take too long!

I hope to work you on a summit soon. VK EU conditions around 0600Z for a few hours are becoming reliable, even for QRP to QRP contacts.

Paul VK3HN.

Hi Glenn

It was perfectly fine and I did not mind the #activationfail at all, more than worth it for the exercise. I’ll get back there sometime over this summer.


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