Project TouCans Lab Notebook: Fixing a Power(?) Short

I had an interesting failure with TouCans a day ago.

TouCans handily activated a park a day last week. Then, yesterday, when I pulled on the antenna wire just a bit, (I promise), the RockMite keyer rebooted which is never a good sign. I adjusted the wire again and the rig audio went off. What had actually happened was that the power supply had shut itself down. I inspected the interior of TouCans and immediately wondered if the power leads to the Tuna Topper ][+ amplifier had shorted on the tuna can. I unhooked the power lines to the amplifier and tried again nothing. Leaving the power lines detached, I decided to check if the power supply would take a charge. It would. I tried again and the RockMite, (as evidenced by its keyer), booted!

I left everything for a bit before, this morning reassembling the rig with the power lines to the amp re-attached along with the RF output line that I had accidentally broken in the process. I checked the bias voltage to the power transistor, for the record, and it is sitting at 3..43 Volts. I put the antenna back on, waited for the F2 layer to get right with itself and...

The rig is back up and running!

It did, however, reboot the keyer again when I was adjusting the antenna. I am unclear why this is happening. The rig was not keyed during either reboot. I now have a layer of tape on the inside of the tuna can near the power supply leads. I will keep you posted.

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