Hytera CPS Modification UHF-H to UHF-L

[AESFTW]

Hello all, I have a 782G mobile in the UHF High Split band. I am looking to see if there is a way to edit CPS to allow Low Split programming. I assume it is a simple hex edit but haven't played to much with Hytera. That being said, I am also looking to see if anyone has created a programming cable utilizing the DB26 port.

 

[romanr]

1. I have built a cable to program MD782(G) mobiles using the DB26 port and I have had no problems programming these radios. A quick Google search yields this: Build your own Hytera cable – PH4X

2. Software defined radios have created the mentality that any radio circuit can be made to work on any frequency by simply changing software.
The current state of the art using real world designs that can be manufactured profitably is a bit more limited.

Filters, oscillators, and other blocks in a commercial quality transceiver that has to meet FCC Part 90 (or similar performance standards) at reasonable costs, will all have limitations on the frequency range in which they will meet those performance standards.

While it is sometimes possible to hack the configuration code to force the radio to operate outside of the range for which the circuitry was designed, you should expect a degradation in performance (reduced receiver sensitivity, reduced transmit output power, increased levels of spurious emissions, increased sensitivity to interference, reduced frequency stability, to name a few...)

I understand what you are trying to do and why. For ham operations, it might be possible and the performance may be acceptable - especially since you probably aren't going too far down below the limit of the UHF High Split. I'm not trying to rain on your parade - just hoping to adjust your expectations. A quick google search came up with this:

HYTERA PD782 Bandsplit Hack changes

HYTERA Canada MotoTrbo DMR Ham Radio. Digital Mobile Radio (DMR) was developed by the European. MOTOTRBO has features than a standard DMR radio

hytera782.blogspot.com

MODERATORS: If the links included violate policy, please delete and accept my apologies.

 

[alcahuete]

As romanr posted, it's actually really easy to do. No hex editing involved, just edit plain text files.

However, keep in mind that unlike Motorola radios, the Hytera is not going to go that far out of band. If you think you're going to go from one bandsplit to another, it's not going to happen. On my 782Gs, the PLL will not lock over about 5 or 6 MHz out of band, and you get an error and that annoying continuous beep. I'm guessing you're going to try to get a high split model into the ham bands.

I would try it. You may have different results.

 

[AESFTW]

As romanr posted, it's actually really easy to do. No hex editing involved, just edit plain text files.

However, keep in mind that unlike Motorola radios, the Hytera is not going to go that far out of band. If you think you're going to go from one bandsplit to another, it's not going to happen. On my 782Gs, the PLL will not lock over about 5 or 6 MHz out of band, and you get an error and that annoying continuous beep. I'm guessing you're going to try to get a high split model into the ham bands.

I would try it. You may have different results.

I was able to make a programming cable and update firmware successfully.Yes looking to get it down into the ham bands. What files am I editing? Thank you.

 

[alcahuete]

I was able to make a programming cable and update firmware successfully.Yes looking to get it down into the ham bands. What files am I editing? Thank you.

Honestly, that's something you're probably going to have to search for, for the exact details. It has literally been years since I've done it, and I don't remember all the details. If I recall, it's simply a matter of editing the model.dat inside the .zip files (in the Hytera CPS directory). I believe you find your model number in the model.dat files and simply edit the frequencies. So for example, if yours is 450 MHz to 480 MHz or such, there should be a 450 (or many of them) in plain text in that file. Simply change it to whatever you like, i.e. 420.

Hopefully someone else with more recent knowledge will be able to help with that. Also, I don't know if it works with the newer firmware. I'm still on 7 with all my Hytera gear.

Actually, looking through some of my files here, that's exactly what I did. So my model had the following bandsplit in the model.dat: Freq2=400,470,400,470,17 I modified it to show: Freq2=400,527,400,527,17 Like I said, it won't cover anywhere close to that, but I just needed a little bit.

 

[AESFTW]

Honestly, that's something you're probably going to have to search for, for the exact details. It has literally been years since I've done it, and I don't remember all the details. If I recall, it's simply a matter of editing the model.dat inside the .zip files (in the Hytera CPS directory). I believe you find your model number in the model.dat files and simply edit the frequencies. So for example, if yours is 450 MHz to 480 MHz or such, there should be a 450 (or many of them) in plain text in that file. Simply change it to whatever you like, i.e. 420.

Hopefully someone else with more recent knowledge will be able to help with that. Also, I don't know if it works with the newer firmware. I'm still on 7 with all my Hytera gear.

Actually, looking through some of my files here, that's exactly what I did. So my model had the following bandsplit in the model.dat: Freq2=400,470,400,470,17 I modified it to show: Freq2=400,527,400,527,17 Like I said, it won't cover anywhere close to that, but I just needed a little bit.

I appreciate it, I will do some searching.