Blaise

The Retevis version of its little brother (DB20-G), the RA25, is also at a significant discount for $92. And: the Radioddity GM-30 is less than $30 the UV5Rs are going for about $15 the QUANSHENG UV-K5 is $24

And yet here you are obsessively testing new equipment and posting instructional videos online! To be fair, I guess you've made GMRS more of a job than a hobby...

I was randomly scanning the other day, and heard: OP1: Do you have any idea why sandwiches are so popular in <local town>? OP1: Well yeah! They're all F***ing inbred! I'm pretty sure it violated at least 2 FCC rules, but I laughed so hard I nearly drove off the road!

If only we could get all manufacturers to put the same default CTCSS tone on all simplex channels...

You have a Grindr call sign?

Just grab some old phones on ebay/craigslist. Much cheaper and easier to store/move/organize...

Well as I said, I don't. I can't hear my phone *ring* at that range with the ring volume on max, so it seemed reasonable to assume that the speakers can't reach that far. It's certainly possible that the ultrasonic frequencies penetrate farther through my house, I suppose. With a dog, a wife, and two rugrats constantly thundering through my environment, opportunities to test are few and far between, so I haven't had the opportunity to implement more variable-controlled experiments yet! Although, if this app can actually send data 20+ feet through doors and down stairs in your home just using your phone speakers, that would be pretty amazing in and of itself!

I didn't think you were. I freely admit that I barely know what I'm doing, and that my methodologies are questionable. It's certainly possible I tested it wrong. putting a radio down a flight of stairs and in a room across the hall is hardly a variable-isolated testing environment. Maybe the phone picked up the sound directly, or maybe the app wasn't really transmitting at 20kHz. I just tried some shit, and it worked, so I based my opinion on that observation without really analyzing it! If you load the app, there's a menu option for "Danger Zone". If you go in there, you can turn on ultrasonic transmission. If you then pick a high sample rate (up to 48kHz), you see lots more frequencies in the Carrier Frequency list, as high as 23,200 Hz. Now, I have no way of validating that these numbers are *true*. All I have to go on is that it *said* it was 20100 Hz. When I didn't hear the data burst, but a message arrived, I just assumed it was true!

Yes. That's the point. We're talking about the sound frequency, not the radio wavelength. You can't have an "ultrasonic" radio frequency, because "sonic" means sound, not EMF.

I did not. I set both apps to 20100 Hz, set them next to radios a couple of dozen feet apart, pushed the PTT, and clicked send, and confirmed reception. I simply took the app's word for it. In fairness, I could only hear a little crackling, not the usual data-burst, so I'm *pretty* sure it was ultrasonic, but otherwise, I did not have a proper experiment set up, so I can't truly confirm anything...

I feel like you might be missing the joke...

My kneejerk response to this is: So? Who cares? My dishwasher wasn't "intended" to be a sterilizing kiln for my homebrew beer-bottles, but it works great at it, and gives me a lot of added utility. The decorative tower on my rescued Victorian home wasn't "intended" to be an antenna mount, but it does a fantastic job, and gives me a lot of added utility. The internet wasn't "intended" to be a corporate-dominated wilderness of false information and endless scammers, but... OK, that one's a bad example... My more thoughtful response is: If something is intended to "facilitate our activities", and we find a new way to facilitate our activities with it, isn't that the very definition of "intended"?

This. I was able to send a message at 20100Hz over a Talkpod to a Baofeng. Is that not supposed to? My methods are hardly scientific...

Hey! Don't be insulting. We're a lot more than just comical or naive. Some of us are *both*!

Compared to the DMR crap regularly blotting out GMRS channels for hours at a time, I would think that a few 1-second bursts per minute at ultrasonic frequencies would be a trivial concern!

Ooohh, I never thought of that, the error correction would eliminate most of the issues you get with a weak or spotty signal...

Yeah, I found that post yesterday, and read the discussion. The app is just a technology demonstrator, to show you can send data easily and quickly with Ribbit. It works like a charm, too! I can see pairing this tech with vox mode to set up on-the-go networks with uplink stations miles apart with nothing but cheap HTs and laptops, at the very least...

I saw the post about Ribbit yesterday, became intrigued, and got lost down an ODFM rabbit hole for a few hours, but then, I loaded the Rattlegram App on two phones, put a phone/GMRS radio in another room, and sent a text message between two phones over GMRS radio. It was really cool. I'm addicted. Links: https://www.ribbitradio.org/#/ https://www.youtube.com/watch?v=ubPP48ojJ3E Also, anyone have any idea what it might be useful for, so I have an excuse for all this time I'm wasting on a burgeoning new addiction?

Just vanity operators...

Do you even YouTube, bro?

Desense is a possibility. I've only tried it from opposite sides of the house, as that's the farthest I can hear from, and my family is utterly uninterested in being a part of this madness, as my wife puts it... But if it *were* desense, wouldn't I not receive the repeater's tail, either? Or is that fraction of a second enough for things to de-saturate?

I've noticed some repeater weirdness too. I can open the repeater just fine, but a local handheld doesn't receive the audio. However, multiple radio-checks confirm that folks *not* in my house are receiving the audio from my repeater calls...

My gosh! He's in so much trouble he has to write an essay?!?!? Apparently the FCC's enforcement arm used to be a high-school principal...

Everything I have has only scan on/off per channel, not groups or anything. I haven't tried that. Maybe I should set up an experiment...

This is the exact thing. Like I said, not a major issue, but maddeningly incomprehensible. Happens on both my HTs and my mobile. I've started keeping tallies in my head to see if this is just perception bias, but it still seems to work this way!