DSDPlus Please make suggestions or corrections to my "Capacity Max Discovery Process"


Apr 8, 2023
Reference System: ERS Wireless Indiana Trunking System, , Indiana
***Assume the system above is not documented and everything was collected from scratch as I am learning to document without help from the RR database***

I've read somewhere that this system is going to eventually replace the one found here. I thought I might try to get a head start on contributing to its page. I have matched a few frequencies to their channels so far but they system only seems to have one... active... talkgroup at this time. I was hoping someone would be able to double check my formatting and workflow as I've never worked with Capacity Max before.

After reading the dsdplus.txt, I was able to find the section on "DMR TIII handling". Following its guide, I first connected to Site 003 (3). This gave me the SysCode for Site 3 as well as the SysCodes for the neighboring sites of 1, 4, 8, 9, 11, 16. The results are below:

10.1010.00001000        (These are in no particular order)

I then got a little confused with this section:
To determine the correct field sizes, gather as many SysCodes as possible by monitoring system sites and examining their neighbor lists ... It becomes clear that the SysCodes should be decoded as (example given).

I tried replicating the format that was used in the example by having the Service Area as 5 bits and the Site Number as 3 bits.

10.1010.00000 001    163       NID=11 Area=1 Site=2
10.1010.00000 011              NID=11 Area=1 Site=4
10.1010.00000 100    499       NID=11 Area=1 Site=5

10.1010.00001 000    1971      NID=11 Area=2 Site=1
10.1010.00001 001    2019      NID=11 Area=2 Site=2
10.1010.00001 011    2033      NID=11 Area=2 Site=4

10.1010.00010 000    1         NID=11 Area=3 Site=1

I continued with updating the DSDPlus.networks file:

TIII, L10, "ERS Wireless Indiana", 5

DSDPlus did not like this format. I tried "TIIInonStd" because I noticed that it auto decoded each of the control channels to this and it worked:

TIIInonStd, L10, "ERS Wireless Indiana", 5

I went on to the DSDPlus.sites file and entered the following:

    ;    ERS Wireless Indiana
TIIInonStd, L10, 1, "Location ?"        ;CC    163
TIIInonStd, L10, 2, "Location ?"        ;CC    583
TIIInonStd, L10, 3, "Fort Wayne, IN"    ;CC    525     454.2750    DCC 0
TIIInonStd, L10, 4, "Location ?"        ;CC    499     454.1125    DCC 0
TIIInonStd, L10, 5, "Location ?"        ;CC    2203    464.7625    DCC 3
TIIInonStd, L10, 8, "Location ?"        ;CC    1971
TIIInonStd, L10, 9, "Location ?"        ;CC    2019
TIIInonStd, L10, 10, "Location ?"       ;CC    127
TIIInonStd, L10, 11, "Location ?"       ;CC    2033    463.7000    DCC 9
TIIInonStd, L10, 16, "Location ?"       ;CC    1

After all of that I sat on a control channel and waited for some channel numbers to pop up. I found their corresponding frequency and entered it like so:
TIIInonStd, L10, 3, 562, 454.5000, 0.0, 0

I re-verified that the match was correct and moved on. All were listed as "nonStd" until I came across a different site that DSDPlus was decoding automatically as "TIIIStd". I tried entering it as:
TIIIStd, L10, 4, 2032, 454.7125, 0.0, 0

An error told me this was the wrong format so I forced it to nonStd and that seemed to work. What I found really annoying was the frequency for Ch 2032 sits right on top of a decently strong NEXEDGE control channel.

So this is my process so far. I am very open to suggestions and critique as I am trying to get better.


Premium Subscriber
Dec 13, 2000
To me it looks like you are doing exactly what you need to do for an unknown system.

I would recommend that you generate the bandplan for the system. You are fortunate as it appears that one is used (as opposed to channel numbers such as 1, 2, 3, 12, 13, 14, etc)
Some folks like using the link floating around to calculate channel numbers, I prefer using Excel as I can get it to calculate the whole thing at once.
Creating an Excel bandplan:
In cell A1 I type 1. In A2 I type =A1+2 The result is 3.
I copy that cell and paste it in the next 1400 cells. The results is a list of DSDPlus channels. You then take your known one and put the frequency next to the known channel.
Next, type 463.7000 next to Channel 2033 ( I believe line 1017, so add the freq in B1017).
You then type in the cell above, =B1017-.0125 Then copy that and paste in all channels above to B1.
Now do the same thing in B1018 but use =B1017+.0125 and paste all the way to B1120.
Once you have that, look at another known Channel number and verify that it matches with the known frequency. I like to have one from each range match to be sure.

I also sometimes use a second radio running, either a scanner in limit search mode or a SDR with a program that has a spectrum display. It makes it easier for me to match channels and frequencies if I don't have a band plan or the system doesn't use one.