• 2026
  • Feb
  • 9

Checking out some recent acquisitions - #7 - The Jackson 710 Selenium Rectifier Tester

Here’s an odd little device from a different age…this is a Jackson Model 710 Selenium Rectifier Tester. Manufactured by the Jackson Equipment Company of Dayton, Ohio, this is a single-purpose instrument in an attractive case. It was purchased at the Columbus Hamfest for $1.00.

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There’s not a whole lot inside of it:

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It even has it’s own little selenium stick rectifier at the top.

The business end is the massive multi-tap transformer inside the thing. This is what’s giving it weight.

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It also has this cutely named “sele-rater” attached to one of the crumbling leads. I assume this is so you can determine (by physical size) what kind of rectifier you have in your device.

So, does it work? Here’s a selenium rectifier removed from the recent PACO G-30 rebuild. I know it’s still a good device, as it was pulled from a working unit.

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Hooking it up and trying every combination of switches I can, I get no deflection on the meter. Ok, so what’s on the outputs of the device?

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There’s pretty much nothing on the output, whereas there should be 130V under test. That tells me the selenium stick is probably bad. No surprise.

What’s going to happen to this? Well, it goes back together for now. It’s not a terribly high priority for me as it’s more of a “that’s cool” device. If I can find an appropriate rectifier at a show, I’ll drag it back out and fix it just to make it work. Otherwise, it’s an interesting display piece, and nothing more.

Next part of this series: Coming soon.
Previous part of this series: https://wereboar.com … c-heathkit-blue-box/