Category Archives: Electronics

Electronics tinkering, repairing, or general tomfoolery.

by srhuston

Fixing a Hole

I’m fixing a hole where the rain gets in
And stops my mind from wandering

–The Beatles, “Fixing a Hole”

For a while I’ve had an old HP 3435A desktop digital multimeter. Picked it up at a surplus place for $60 so I could have a meter that sits on a shelf and is always ready, doesn’t need batteries, has a decent readout, autoranging, basically a bunch of features that my existing meters did not have. Recently when I went to use it, I found that the voltage it was showing was impossibly wrong – I seem to recall it was an AA battery I’d just removed from something marginally working but it read 0.2V – and then shortly after the only thing it would display is “OL”, its code for out of range. Around the same time as that, I saw a video from Great Scott! that talked about a portable DMM that also has a two-channel 50MHz oscilloscope. Now I already have an old analog scope here, but .. well, it’s old, and it doesn’t have a lot of the nice features that newer scopes do. So after getting that new meter in my hands, I decided recently to take the old one apart and see if I could find out what was wrong with it.

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by srhuston

Microphone Switching for Fun and Profit

When I started in amateur radio, I did the simplest of things – used the hand mic plugged into the front of the rig. Over time, I drifted away from radio usage for a bit and then came back into it (that’s a story for another post.) When I did, I started to make my shack more complex and versatile, and even added new radios for more functionality. Now I had the problem of having different ways of talking into different radios, and I didn’t like that as much. So I designed a switch box that could take some inputs and mix up the outputs to make things more convenient for how I like to operate. I had someone on my radio club email list ask about a product that could do a similar thing, and I mentioned that I built one for not that much time or money. Since he was interested in more information, I wrote the whole thing up as a nice article. And now, I present it to you, my Home-Made Microphone Switch.

by srhuston

Getting There, and What’s Up

I’m starting to get there with the site layout. Adjusted some things, I think I broke some things too, but it doesn’t look half bad. Except the black text in the top bar, I don’t think I like that. Maybe I’ll play with other themes and see if I find one I like soon. Meanwhile, back to the topic of “why are you reviving this”, some information on ideas I’ve got and whatnot. Strap in kids, it’s gonna get bumpy.

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