This has been a recent hot topic on the
Digitrax Yahoo Group and the
JMRI groupBoth are useful.
The PR3 is the most versatile. It has 2 modes - MS100 emulator for connecting your computer to Loco-Net and Programmer mode for programming without a command station. In addition it's the only thing that can download sound files to the Digitrax sound decoders - so far. It also has the reputation of being a bit finicky. Digitrax tech support on the device has the reputation of being fairly useless unless it's a really simple problem. Have a spare USB cable handy as a good number of the ones sent out with the device are known to be bad. For MS100 mode it needs no power supply, but for standalone programming you need at least 14vdc and closer to the max of 20vdc can be better if you need to program "foreign" sound decoders like the Tsunami.
The Locobuffer-USB is a pure computer interface. It will tie your computer to the Loco-Net bus and do it very well. But that's all. Since you (will) have the Zephyr for programming you are okay there. DecoderPro (JMRI) will use the LocoBuffer to to talk to the Zephyr and do the programming. The LocoBuffer has opto-isolated inputs which can be a factor if you have electrical ground issues. The manufacturer, Dick Bronson, hangs out on both the Digitrax and JMRI Yahoo groups and is very helpful if you should have a problem, but they are rare. If size is a concern, the LocoBuffer is a lot smaller. It's powered off of the USB port. The USB chip used in the LocoBuffer (or maybe the drivers) provides a unique registration id which is handy in Windows - if you plug the LocoBuffer into a different USB port on your computer, the COMx port won't change whereas with the PR3 it may. A minor, but often frustrating problem which comes up on the groups.
I am also a Mac user and I have both of these devices. However, at the moment my usage of them is almost nil and I'm relying on what I have read over the past year or so on both of these groups. With any luck, in the next few months I'll have thing set up and I'll be doing a lot with them in terms of programming and learning JMRI.
If you have any interest in using the Digitrax sound decoders - primarily downloading new sound files, then you need the PR3 as this is the only device that will do that currently. The caveat is that the only programs that work with it are mainly provided by Digitrax and they are Windows programs. Digitrax has no interest at this time in providing Mac versions. However, there is work being done with JMRI to accomplish this task. Currently it is beta (maybe alpha) level.
If you have the means, getting both is not a bad idea. If you want something to start with, knowing what I think I do about your situation from reading this message board, I'd say start with the LocoBuffer-USB. It's the easiest device to use to link the computer and Loco-Net and you can use it, JMRI and your Zephyr to do programming. Later on if you decide you need a stand-alone programmer or want to do Digitrax sound, then you can get a PR3. If you decide to get the PR3 and want to use it as a programmer, remember you also need a power supply - either a Digitrax PS14 or equivalent. It's not included with the PR3.
John H. Reinhardt
