Hi All, I've received my Interface and starting to prepare the Blackbox per the instructions. The first step has me removing the Q25 transistor near the USB port. Before I remove Q25 I would like to know if its removal will cause any issues if I revert back to a PC for any reason? I assume Q25 is there for a reason and therefore removing it may cause something else not to function if removed. What are the side effects of removing this and using a PC? Thanks - Steven
As explained in docs:interface:prepare-blackbox-v2.3-2.6 [OpenBuilds Documentation] "This modification allows Interface to communicate with the BlackBox V2.4, V2.5 and V.26 boards via AUX1. It does change one behavior of the BlackBox - it is no longer powered over USB - so the 24v power will need to be connected and turned on whenever you want to work with the BlackBox. As you need 24v connected and switched on for the stepper motors and other accessories as well, it will not be a noticeable difference to most users." It will still connect to the PC just fine!
Thanks, Peter. My concern was about the part where it states, "... it is no longer powered over USB - so the 24v power will need to be connected and turned on whenever you want to work with the BlackBox." I'm usually too literal so wanted to make sure that removing Q25 was not also removing the ability to power the Blackbox with USB if using a PC after the modification. Out of curiosity, what does Q25 control if it can be removed without any affect on the Blackbox? Thanks - Steven
Q25 is a "switch" that switches the 5v rail between being powered off the USB port, or the internal regulator. Removing it just forces it to stay on the internal regulator, which also helps the MUX switch over succesfully between USB and AUX - Q25 had a little leakage current that kept the Mux on USB mode even after Q25 switched.
It does remove the ability to power via USB, but not the ability to connect from your PC. You can connect from the PC directly to the Blackbox, but you must have the power connected and turned on. (Just like you would if you were running a job. No one should notice, because you anyway need the 24v power for the motors, etc to be on)
