Demo of a working replica of the Great Seal Bug on the 23cm band

This is a demo of a working replica of the Great Seal Bug.

As far as i know this is the only attempt to make a working replica, not only a nicely looking prop.

I am a licensed radio amateur (callsign SQ5BPF), therefore the device dimensions were scaled to make it operate on the amateur radio 23cm band (1240-1300 MHz).  Please see my other articles about this device.


The Great Seal Bug. Part 3: Building a working copy of The Thing

This is the third part of articles about the Great Seal Bug (also called “The Thing”). These articles will cover: history, theory of operation and a practical reconstruction of this device. This part is about building a working copy of the Great Seal Bug

To my knowledge this is the only publication about making a wirking replica of the Sreat Seal Bug. shows a beautifully looking model, however the emphasis was on making it a nice looking exhibit, and not on making it work (but look at this site anyway, the model is a work of art).

In 1945 this was super-secret, ultra-novel military technology. Building and operating it required special materials and access to ultra-secret hardware. So is it possible to do this in 2022 on an amateur budget? Surely not.

But radio amateurs have a long history of doing “impossible” things, part because of their ingenuity, and part because of their ignorance (they simply don’t know something can’t be done). So lets try anyway 🙂

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Astec AA21660 power supply modification for 13.8V output

Astec AA21660 power supplies can be modified to give 13.8V / 24A.

They are specified to 24A @12V and 27A @5V, with 400W max continuous power. It is used in various  Engenio (former LSI Logic) storage products, which are OEM-ed by many companies: IBM (TotalStorage DS4xxx and DS5xxx line), NetApp etc. The IBM FRU is 19K128.

The following mods change the overvoltage protection to 14.4V, and set the voltage to 13.8V.

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