Spares for the shack?

Last October, just as DX was starting to get good, my big-ole Astron power supply gave up the ghost. Or so I thought. Turns out it just wanted to nap for a while…several days. I took it apart, schematic in hand, to see if I could find an obvious fault. I thought one of the pass transistors might be the problem.

Not finding anything, I buttoned it back up and, to my surprise, it came to life and has been working like a champ ever since. Previously, I’d cycled power several times in the hopes that the crowbar circuit simply needed resetting. To this day I have no idea what the problem was or what fixed it.

But it got me to thinking – what if that had happened just prior to CQWW or a DXpedition to someplace I need? I’d be SOL.

The main power supply is my weak link. I can quickly string another antenna, several keyers are on hand and another computer can be brought in for logging/keying if need be. And I do have a small 7A supply which would probably be good for 30 watts out of the K3 – not what I have in mind for the Swains Island DXpedition, CQWW or other major contests that I plan for.

My current and prior jobs are lessons in redundancy. You’d be amazed at how many ways a modern submarine has to get to the surface. Even the back-ups have back-ups. Same with my current job.

So my back-up power supply is now a bank of 12V deep cycle batteries that live in the garage until (and unless) I need them. Enough juice to see me through a weekend of contesting. Or a hurricane-driven power outage.

I didn’t buy them for that purpose but they are available for it.

There’s no way I can buy a $300 power supply or a $600 rotator simply to sit as a spare, waiting for a problem. I think a person’s dedication to the hobby can be measured not by what he spent on his operational gear but rather by how much he’s invested in spares.



  4 comments for “Spares for the shack?

  1. August 13, 2012 at 12:24 pm

    I use my spares as a second station for SO2R ;o)

    Seriously: I try to keep things symmetrical for backup and for troubleshooting. Always handy if you have a working device at hand when trying to fix a broken one.

    I have two K3’s and two identical SMPS, and identical band decoders. If it weren’t for the heat and the 747 jet fan noise, I bought a second identical amp too. I have no spares outside (tower / rotator / antennas).
    I must say I have considered a spare rotator. I keep my eye open for a bargain on the local classifieds.

    • August 13, 2012 at 4:05 pm

      I do have two other commercial HF rigs but have been so spoiled by the K3 that if it failed during a contest I’d just consider myself QRT. For an ATNO, I’d pull the old FT840 out of mothballs.

  2. August 14, 2012 at 5:40 am

    I do like ON5ZO but don’t have the antennas yet to actually do SO2R:

    Left side is “K-line” and all my new stuff.

    Right side is all my old stuff: TS-850, Titan Amp, MFJ manual antenna tuner. I usually only turn this side on in Sweepstakes or when there is an ATNO on the low bands and I want to run 1500w instead of 500w. The K3 does spoil you.

    In between are the single points of failure: Astron supply, MK2R+ and the PC.

    At hamfests and online I’ve picked up used spare Astron and Microham and have my old Windows XP shack PC still available as a spare. I had to use the spare MK2R when original one failed, luckily within warranty period. I bought the Astron when I bought the TS-850 (1991) and it failed once back in the mid 90s, been no fuss, no muss since then.

    73 John K3TN

    • August 14, 2012 at 6:54 am

      After writing this post I realized that even though my 7A supply will only provide 35 watts or so out of the K3, that 35 watts will drive the amp to 500 watts. I guess I have more redundancy than I thought, though not even close to SO2R here – hurts my brain to think about doing that!

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