Saturday, June 24, 2017

Velvet Ant vs Ziploc Bag

About a week ago I saw a weird bug walking away from a wood pile. It looked dangerous so I caught it in a ziploc bag. It turned out to be a velvet ant. Its jaws were so powerful that it stretched and nearly punctured the bag when I held it taut. Knowing nothing about velvet ants, I didn't realize that the jaws were the least of my worries. I did not know I had to watch out for a stinger, but thankfully I wasn't stung.

As you'd expect by the bright coloring, an article described the pain of their sting as "life-changing, pray-for-death pain". Here is a YouTube video of someone being stung by one:

Needless to say, I was glad to have caught it in a bag. Eventually the bag was placed under a basket on a table and forgotten.

Then today as I entered the living room I saw a bug running across the table. I thought it was a roach and hit it hard and flung it down so I could get a clear path to kill it. But after getting it onto the floor, I realized with horror that this was not a roach, but the velvet ant! Quickly snatching up an envelope, I put it on top of the retreating wasp (that's what they really are) and delivered one quick blow which instantly killed it. It was running to the edge of the table and if I had entered the living room just 5 seconds sooner or later I would've missed it.

Apparently velvet ants can escape from ziploc bags. Here is a picture of the hole it made:

Monday, June 12, 2017

Faulty Marvel Walkie-Talkies

Recently I had the chance to test some children's walkie-talkies. These are generic blue walkie-talkies that can accept plastic front plates with Marvel characters. The label did not specify the frequency but a quick Google search for the FCC ID, 08KAK-2, revealed that they operate in the 49 MHz band. However, that's not where they actually operate...

I played a song on YouTube while holding down the talk button and this is what I got:

(The vertical bars are my LED monitor)

Apparently, this is an incredibly unstable oscillator that actually operates in the 6 meter ham band.

Because of the waterfall, it was trivial to figure out that this was FM. While the width appears to be around 24 kHz here, it can go up to 75 kHz when you blow the mic.

I'm really surprised that the other walkie-talkie can pick up the signal, considering how the transmitter jumps around not only each time you push talk, but even as you're transmitting.

As a ham (Extra class, by the way), I know I would HATE seeing something like this in the 6 meter band. But since the toys work despite their instability, I would expect any narrow FM in this range to "bleed" into the toy's passband, so kids should hear any hams they're interfering with.