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Hytera PD782U-5 on 900MHz Amateur Band

Has anyone determined how to put a US version (NA2) of one these nice U5 split radios on 902-927? The freq range on the label says 806-941, but unlike other Hytera DMR radios, the frequency span is not continuous. It's broken up into 4 bands: 806-824, 851-869, 896-902 and 935-940. When you look at the Model.dat files in the CPS the entire range is defined one entry like "806-941,806-841,21" Any explaination on how they are further partitioning the span? Is it done in the CPS.exe binary? I have looked around a fair bit, and have no idea yet how it's being done. When a frequency like 927 MHz is entered into the CPS, an out of band message is displayed and the number defaults to 935 MHz. A number like 902.5000 gets the error message and is changed to 902.0000 You can enter any frequency within the 4 defined bands just fine. The original CP was programmed with a repeater pair that had the RX in the 851-869 band and the TX in the 806-824 band with a 45 MHz offset. I was expecting to see these four frequency ranges defined in the Model.dat file, perhaps in several different entry lines. No such luck..
I did a hex scan of version 8.01 of CPS.exe and saw nothing that looked like ASCII coded freq ranges. Also examined the codeplug file with the hex editor thinking I might be able to change frequencies in the file and reload it into the radio, but it appears the file must be encoded in some way. Nothing is recognizable. 

Also, what is the number (21 in this case for 806-941) at the end of the entry line in the Model.dat file entries? It's a "1" for the VHF radio, a 19 for 350-400, and a 17 for 400-470. It makes no sense to me. Ideas or theories about these mysteries would be appreciated.


When I mentioned the number at the "end of the line" I was referring to the line in the Model.dat file, not the last digit of the model number of the radio that designates region. In that file, there are entries that define a radio radio's long model number along with a frequency range for RX and TX along with this 'mystery' number I mentioned. An entry might contain a line like "400,470,400,470,17" If you wanted to extend the range to say 475 MHz, you would edit the entry to 400,475. So one question I have is what does the '17' denote?

I also have a PD782G-U2, a high split 450-520 radio with older (5.x) firmware. With the older version 5 CPS, there was only one Model.dat file in the /Program Files/Hytera/Config directory that needed to be edited to extend the range down into the Ham band. With the newer versions of radio firmware and CPS they changed the file structure, and now there are a series of zip files named r10 to say r80 that correspond to various FW versions. So r80 for example, has the Model.dat file for ver 8.0x firmware. Normally, you would unzip, edit the Model.dat file and then re-zip it.

On the U5 806-941 radio, despite the band being segmented into four areas, with 902-935 'locked out', the appropriate Model.dat in CPS only shows one entry for the whole range, namely "806,941,806,941,21" So how do they develop the segmentation with only one entry? Clearly, another mechanism is at play. One possibility is when a 900 MHz range codeplug is read, the channel entry limits in the CPS get modified, or perhaps it hard-coded in the CPS binary, or something else entirely. It is at the CPS level, because you cannot get past entering the frequency into the channel parameters. It's not like an error in writing the CP to the radio. You don't get that far.

 

 

Update:

If your radio is on version 9, then the model.dat method no longer works. I’m not aware of a supported (or unsupported) method for downgrading. Otherwise I would suggest doing that. 


If by some chance you’re still on version 8, there’s a good chance that method will still work. It’s been a long time since I did it. 

 

Note:  they split the range 806-941 range in 4 parts. I just looked and it seems that Motorola does the same so it must be an FCC thing.

 

https://digitalhamradio.groups.io/g/main/wiki/27959

https://groups.io/g/AmateurRadio/wiki/27960

https://hytera782.blogspot.com/2021/06/hytera-pd782u-5-on-900mhz-amateur-band.html#more

 

software:

https://groups.io/g/AmateurRadio/files/Hytera

i have the software in another group (AmateurRadio), yes poor planning.

 

Hytera PD782U

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