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 variousĀ  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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SV9/SQ5BPF with uSDX part 2

So I’ve tried to operate from Platanias / Crete (see SV9/SQ5BPF with uSDX part 1).

Threw a wire on a palm palm tree, stretched a counterpoise on the ground, tuned it, and made the first CW QSO on 40m with Zygi SP5ELA. So next I’ve tried to tune the antenna on 80m, and the uSDX transceiver failed with a short circuit.

It seems that the smd PA transistor died on 80m (it also dies on 10m). Fortunately I’ve had two IRLML2060 transistors with me, but no soldering iron and other tools.

So is there any hope that i will be able to make more than one QSO?

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