More about Tuna Topper Shielding aka Tuna Soup

A bit more about shielding the Tuna Topper amplifier with a can of Progresso soup.

I tried a shielding experiment here at the home station today, and had great results. There was in fact no reductcion in output power. It's unclear to me if there's a reduction in general noise yet. There are roofers next door, and their propane heaters are laying down a nice, even, low-level ground floor. Here's a detail picture of the shielding:

The soup can is opened on one end, the soup has of course been removed, and the can cleaned. The open end i placed over the exposed Tuna Topper circuit board. I thought there would be issues with the RF in and out wires being sandwiched between the two cans, but there are not, (at least for this installation.)

I made a contact with AE7CG with the shielding in place. Here's the QSO map:

You can see the signal was reaching out fairly far, but no further than Utah. This is an afternoon thing here in San Francisco that I haven't entirely figured out yet. In any event, the shielding works, it does not inhibit the normal operation of the radio, and it accomplishes one more thing, we have a mist and fog problem in San Francisco. Don't get me wrong, the mist and fog are actually quite nice, but they wreak havoc on exposed circuitry. This is a step in the right direction to being able to leave the radio out all night again!

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