[Suggestion] GPS Distance, Repeater Coords, & Channel Sorting

[KQ4IOE]

I ordered my first DMR yesterday (TYT MD-UV390) and I'm excited about it coming. I had a few ideas which could be implemented in the firmware relatively easily, depending on how it's structured. These ideas rely on each other, with the first idea being the baseline for the second and third. Disclaimer: I don't have a radio yet, so some of these may already be implemented, or in development. I tried to search for these features before I made this most, but found nothing. Also, I'm young and new to ham radio. I apologize if I sound naive.

I will start with listing the suggestions, then give examples to show why they are helpful.

1. GPS Distance
I think I heard someone talking about this once. Essentially, when receiving GPS coordinates and with GPS enabled, calculate the distance to the other person. Should be a relatively easy and small calculation.

2. Repeater Coordinates
This second suggestion relies on the first: programming in repeater coordinates would let you check your distance from the repeater. You could possibly even have repeater range programmed in. Obviously this would take more space, but I'm willing to lose a few channels to see what repeaters are close to me.

3. Channel Sorting
This is where the three suggestions all come together: An option to calculate and sort all repeaters in a zone by distance (or possibly by name or mode if wanted). When pressing this, GPS would temporarily turn on to find your location, and the radio calculates what repeaters are closest and displays them at the front of the zone.

Where would this be useful?
1. GPS Distance
Say you are talking on a local repeater which supports GPS data. You are talking with someone locally who is sending data. You can see that you are only a short distance from them, and you both agree to switch to simplex.
GPS distance has less useful applications and is really just 1. a cool feature, and 2. a baseline for the other suggestions.
2. Repeater Coordinates
Let's saying you are driving around town, but you don't know what repeater you are close to. By looking at your radio, you can find what repeaters you can hit rather than having to try them all.
3. Channel Sorting
Finally, you decide to take a trip out of state/country. You would usually program in a new codeplug, but let's pretend you have enough space to copy all the repeaters there into a new zone. While you are driving through this different state/country, you have no way of knowing what repeaters you can hit. Sure, you could try them all, but that would take forever. Instead, you just sort by distance. Turns out there was a repeater only 2 miles from you!
This feature is also useful if you have a lot of channels in a zone, and need to sort alphabetically or by mode.

I hope I have been able to demonstrate why each feature I listed could be useful. If I could only have one, number 2 would be my pick. Being able to see where repeaters are is something that would help immensely when mobile.

Devs, thank you for this wonderful firmware. I hope you will give my suggestions a try.

[VK3KYY]

I don't think there is room in the codeplug data format for location data for each channel

There may be a few bytes free, but these are already earmarked for other functionality

Also where do you get the coordinates from .

I just looked on repeaterbook for my local club repeater and it's not even listed

[KQ4IOE]

I don't think there is room in the codeplug data format for location data for each channel

That's too bad. I think it would make a great feature if there was room. I'm not sure how the channels are stored, or whether they each have to stay within a certain size, but I would think you might be able to reduce the number of channels to include that feature. I know CHIRP has channel "comments", but I'm not sure what the size limitations are, or whether they are even uploaded to the radio.

Also where do you get the coordinates from .

Kind of stupid, but: you estimate. By looking at Repeaterbook's map system, or if the repeater owners say where it is, you can get approximate coordinates with Google Maps. Not meant to be accurate, just tell you approximately if you're in its range.

If anyone else has any similar ideas on how people could find close repeaters without trying them all or using the internet, please share!

[VK3KYY]

Kind of stupid, but: you estimate. By looking at Repeaterbook's map system, or if the repeater owners say where it is, you can get approximate coordinates with Google Maps. Not meant to be accurate, just tell you approximately if you're in its range.

Unless there is a dataset that can be downloaded, I can't see more than a few people bothering to ever working out the approximate position of the repeater and entering it onto their radio.

[ZL2MGS]

"If anyone else has any similar ideas on how people could find close repeaters without trying them all or using the internet, please share!"

I might be misunderstanding the question, but on my phone, even when not connected to the internet, the very first line of each repeater entry in Repeater Book is its distance from my current position per the phone's GPS.

[KQ4IOE]

I might be misunderstanding the question, but on my phone, even when not connected to the internet, the very first line of each repeater entry in Repeater Book is its distance from my current position per the phone's GPS.

Wow, I didn't know that! Thank you for telling me. That would pretty much be what I want. Would be cool to have in the radio, but probably not as practical.

[VE4HTO]

The requested features look a lot like the Icom D-Star funtionality. So i did a little fideling with the Repeaterbook website's Export function. If i export all the repeaters in my area (Manitoba) in the ID-5100 Repeaterlist format, the resulting CSV contains all the geo-locations and even a marker "exact" or "estimated". Maybe something that can be used...
BTW to my surprise i found a export option "Radioddity - OPENGD77 CSV", unfortunally without the geo-locations...

73 Norbert VE4HTO

[VK3KYY]

The requested features look a lot like the Icom D-Star funtionality. So i did a little fideling with the Repeaterbook website's Export function. If i export all the repeaters in my area (Manitoba) in the ID-5100 Repeaterlist format, the resulting CSV contains all the geo-locations and even a marker "exact" or "estimated". Maybe something that can be used...
BTW to my surprise i found a export option "Radioddity - OPENGD77 CSV", unfortunally without the geo-locations...

73 Norbert VE4HTO

The GD77 codeplug format does not contain fields for location data, nor does the official codeplug format for any of the other Chinese radios that I am aware of

I checked and there are only 4 bytes free in the channel data structure, so a precise position could not be stored, but possibly an approximate positions to about 1 mile accuracy may just fit

[VE4HTO]

The GD77 codeplug format does not contain fields for location data, nor does the official codeplug format for any of the other Chinese radios that I am aware of

I checked and there are only 4 bytes free in the channel data structure, so a precise position could not be stored, but possibly an approximate positions to about 1 mile accuracy may just fit

even 5...10 miles should be be good enough for the purpose of sorting a list or maybe auto tune to the nearest repeater. ( dreaming of... ) If i remember correct is e.g. FT8 software and it's addition Gridtracker going to use the center of a locator field for displaying the distance. Locator is 6 bytes, ...too long!
Maybe another idea for the CPS only: sorting the channel list based on locator (geo-zoning the channels, maybe auto-build zones) before writing to the radio. Would be useful for whose without GPS...

...just things that came to mind

[VK3KYY]

The GD77 codeplug format does not contain fields for location data, nor does the official codeplug format for any of the other Chinese radios that I am aware of

I checked and there are only 4 bytes free in the channel data structure, so a precise position could not be stored, but possibly an approximate positions to about 1 mile accuracy may just fit

even 5...10 miles should be be good enough for the purpose of sorting a list or maybe auto tune to the nearest repeater. ( dreaming of... ) If i remember correct is e.g. FT8 software and it's addition Gridtracker going to use the center of a locator field for displaying the distance. Locator is 6 bytes, ...too long!
Maybe another idea for the CPS only: sorting the channel list based on locator (geo-zoning the channels, maybe auto-build zones) before writing to the radio. Would be useful for whose without GPS...

...just things that came to mind

Building zones on the fly is too much complexity for what could be fitted into the limited program memory space in the radio. We literally only have a few kilobytes of program memory remaining in the radio and the APRS functionality would probably take priority over other things, as would DMR SMS support if anyone ever wrote it, as would APRS Rx if anyone every wrote it, or Dual Watch (if anyone every wrote it) etc

These radios have the CPU power akin to a 80's home computer , not a modern cellphone, or a RPi or even a RPi Pico.