Reviving this topic after being dormant for 7 months.
It is possible to set up public groups starting at ID = 1 in the DTR600/700 models and in the DLR1020/1060 models, identical to the legacy DTR410/550/650 models. It is VERY easy to do.
I have had a fleet of DLR1060 radios working with a fleet of DTR650 and a fleet of DTR700 radios on public and private groups identical to the legacy DTRs. Public groups started at ID = 1 identical to the legacy DTRs.
The 4 digit Profile ID Number (PIN) feature is a new feature which started with the DLRs when they were released in 2015 and in the DTR600/700 when they were released on November 30, 2018. The legacy DTR410/550/650 models don’t have the PIN feature.
The requirement that public group IDs in the DLRs and DTR600/700 start at ID=21 is due to the restriction that a public group ID can be used only once in the radio. Profile ID groups 1-20 take up the first 20 public group IDs when the PIN is at the 0000 default. The PIN feature is OFF when the PIN = 0000. Profile ID groups ARE public groups when the PIN = 0000. Setting the PIN to a non-zero value even if you are not going to use any Profile ID mode channels causes Profiile ID mode group IDs to become something other than public groups and frees up public group IDs to start at ID=1 identical to the legacy DTRs.
If all of your channels will use the same hopset, leave the Profile ID Number Lock enabled (default = enabled). The CPS warns that disabling this and mucking around with the hopsets used may cause some features to not work and is for experienced users only. I recommend leaving this setting at the default (enabled).
There is some behavior with the PIN feature to be aware of. The last 2 digits of the PIN affect the hopset used by the whole radio. You can get around this by disabling the Profile ID Number lock but I recommend leaving the lock enabled (default = enabled) and choosing a PIN carefully. This assumes all channels will be using the same hopset.
PIN = XXX1 Hopset 1 used
PIN = XXX2 Hopset 2 used
PIN = XXX3 Hopset 3 used
PIN = XXX4 Hopset 4 used
PIN = XXX5 Hopset 5 used
PIN = XXX6 Hopset 6 used
PIN = XXX7 Hopset 7 used
PIN = XXX8 Hopset 8 used
PIN = XXX9 Hopset 9 used
PIN = XX10 Hopset 10 used
I recommend choosing a PIN carefully so the last digit(s) match the hopset you want to use. The default hopset is #1. In my programming, I chose a PIN that ends in 1, i.e., XXX1 to use hopset #1.
Assuming all channels will use the same hopset, there are 2 methods to set up public groups identical to the legacy DTRs and with group IDs starting at ID = 1. There is no need to change any programming in the legacy DTRs.
Method 1: Assuming you are going to use the default hopset (#1), leave the PIN at the 0000 default (OFF) and program channels as Profile ID mode channels. Profile ID mode channels are public group channels when the PIN is at the 0000 default (Off).
Method 2: Set the PIN to a non-zero value, even if you are not going to program any Profile ID mode channels, taking care to set the last digit(s) to match the hopset you want to use. Then program public groups identical to the legacy DTRs with IDs starting at ID=1.
In my DLR programming, DTR650 programming, and DTR700 programming, I had them all working with each other in a mix of public and private groups and with public group IDs starting at ID=1. I also had the DLRs and DTR700s working with each other on Profile ID mode channels too and with Profile IDs starting at ID=1. Method #2 above is the recommended way to program channels when you have a mix of Profile ID channels, public group channels and Private group channels. Private group channels program identical to Private groups in the legacy DTRs.
I like the DLR and DTR600/700 way of programming much better than programming the legacy DTR410/550/650 models. The DLR and DTR600/700 programming is less cryptic than programming the legacy DTRs. I am not surprised Motorola adopted the DLR way of programming going forward.