Thoughts on Flying Batteries

Those of you familiar with Project TouCans can probably immagine where this is headed

Could Project TouCans become Project ThreeCans? Should we have a contest to name the new incarnation?

Here's what's going on. I set out to write it about this on several occasions, but haven't carved out the time. Sticklers for detail may have noticed that the keyer sprouted a pair of 5 kOhm resistors in the last few weeks. I still don't have time to explain it at lenght, but let's just say that left to its own devices, I'm pretty sure that ground at the keyer is a negative voltage compared to ground at the input of the keyer chip that lives inside Project TouCans. This leads to the keyer rebooting itself at best, and occasionally getting so cranky that it just gives up. I believe the whole issue is the largeish amount of current that the Tuna Topper amp pulls down the Ethernet cable that supplies both power and the keying signals. The two resistor make the keyer ground more comnparable to the radio ground, and the reboots go away.

While we're delighted about the amount of current since that's what's giving us a full 5 Watts QRP output, we could do without the keyer reboots. But... What if... Maybe...

Just maybe...

The power supply was a mere two or three inches from the amp itself. Voltage drop on ground issue solved!

And that's where the third can shown above comes in.

I'm not sure the twine supporting our home station can handle the exra weight of the battery. At the same time, it supported the weight of 8 AAs just fine back in May.

8 AAs weigh 10.5 oucnes. The imuto battery pack weighs in at about 24 ounces, so almost two-and-a-half times more. If the twine and the wall bracket can support the weight, this might be worth a try!

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