Project TouCans Slims Down to a Single Power Supply

Up until yesterday, Project TouCans required two battery packs, one in the rig itself to power the Rockmite and Tuna Topper amplifier and a much smaller external one to power the Pico-W that controls the rig's keyer and straight key. I tried bringing a USB A cable directly from the Imuto power bank in the rig out to the Pico-W, but the RFI was too much for the Pico-W causing it to reboot, or just turn off. That led to the two or three AA battery battery pack, which frankly was a bit to much extra weight, and a bit unwieldy.

Thant's all fixed now! I added as second Adafruit USB-C power adapter to the rig and that provided enough filtering that the Pico-W is happy as long as I make sure the rig doesn't transmit at all until the antenna is completely unfurled, which is a pretty reasonable expectation. When/if the rig does transmit with the antenna bundled up, the Pico-W reboots, then it presses the straight key which upsets the rig, causing the rig to reboot, except on reboot, the rig's keyer no longer functions. This is actually a nice failure mode as it breaks what could be an infinite loop otherwise. The rig's USB-C adapter is partially obscured by the USB-C cable that is attached for charging. The Pico-W USB-C adapter can be seen on the right.

Part of the rebuild was facillitated by 3M double sticky foam tape. It made for a simple installation of the Pico-W onto the relays and the relays onto the side of the can.

Detailed picture of the Pico-W mentioned in a previous post. Note that it's legs up and has it's relay and power wires twitsted together and nested between the legs.

Last night, on the initial test of the newly configured rig, I had a QSO with KF6VB across the Bay in Hayward. Our signals were ground-wave, and therefore a bit weak, but the QSO was clear! I left the rig on over night from 03:50 UTC. at 11:20 UTC the rig made a QSO with WX7V in Texas! The power pack lasted over night even with the added load of the Pico-W!

Finally, at about 16:30 UTC this morning, the buck converter in the Imuto power brick finally started to hum indicating it had turned on its switching power supply. I took the rig down to recharge which is what you see it doing above. The USB cable that brings power out of the rig also brings the charging current in.

The new battery arrangement led to no dropped Wi-Fi signals as well. I suspect this is because of a more solid current source at from the Imuto USB-C power brick. Here's the Chromebooks' signal report.

One last thing of note. While the hum was annoying enough for me to bring the rig into dry dock for a charge, the transmit signal was still S9 at the Utah SDR with a noise floor over there between S1 and S2.

S-meter of Utah SDR showing noise floor reading of S1 — Noise floor at Utah SDR this morning

S-meter of Utah SDR showing Project TouCans received at S9 — Project TouCans calling CQ at S9

Here's a rare (the only?) video of Project TouCans looking back up at the home QTH. Note the hill between most of the dipole and the Pacific about 3 miles away. (Yet, TouCans is reguglarly spotted in Hawaii and occasionally in New Zealand. And has a QSO out to Hawaii under its belt.)

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Copasetic Flow

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