VK5/SE-012 Problem with Rig

Thanks to the few chasers I was lucky enough to work today on Mt Horrocks.
Worked all chasers on 80m ssb and cw then got 3 qso on 40m ssb ,changed to cw and got halfway through my first cw contact with VK7CW and the kx3 died. Nothing obvious I could see swapped battery still black screen. That’s a sick feeling especially if some thing major has happened and the closest help is in USA. Packed up and sulked home to do some tests, to find even on the home PS it still wont go after checking in line fuse etc, no continuity on the power lead and the shack power lead started the kx3 straight off. Well that’s a great relief. Turns out under the tape where I soldered the inline fuse holder 6 years ago, the wire has cracked off at the now daggy old solder joint. Up shot is I can fix that and it will give me something to do this afternoon after I submit my log. How lucky was I to get 6 or so QSO’s before it finally broke.
Hope to catch rest of my faithful chasers on the next one
Ian vk5cz …

1 Like

Ah, yes the old do you solder or crimp debate. I crimp.

I think whichever you do, it’s a good idea to support the wire close to the joint with some sort of strain relief - I have used a blob of hot melt glue in the back of Powerpole connectors. Heat shrink sleeving is good for in-line joints.

Where the flexible stranded wire turns into a single thick wire (whether that’s because the strands are soldered together or held tight together in a crimp) there is a point of failure.
It probably doesn’t matter in a permanent installation, but for portable work where there is frequent flexing, it’ll happen one day.

Good to hear that you qualified the summit, and no harm done, Ian :smile:


If you really want unreliability tin the wire then crimp! Common rookie mistake.

1 Like

When I worked for a “defence contractor”, connector problems was the #1 reliability issue. This included connectors failing to connect properly or wires into connects failing. We used an extended VME type of bus on computer cards (DIN41612 connectors) but limited them to 25 make/break cycles before both sides were considered defective and were replaced. Replacing them after 25 cycles reduced the number of pseudo-SEUs during testing (we also did have real SEU’s in the customer fit due to the nature of the beast!) and generally meant that a failure was software related not hardware.

It taught me well. It’s not a matter of if a wire into a connector will fail but when it will fail. So solder things meant to be soldered and crimp things meant to be crimped. But don’t mix crimping and soldering together. Most importantly, ensure there is strain relief and flexing support designed for the job in hand or the “when” will happen far too frequently.

But wouldn’t it be thus stronger??

Similar, I use the heat shrink with hot melt glue inside. It’s all about suporting the conductor so it doesn’t take much, if any, of the stress from movement.

'course if your on a summit stripping the wire with your teeth and twisting the wire together is just as good.

There shoud be a bonus point scheme for in field repairs.


1 Like