Looks good Phillipe, I used my boom in the garden at the weekend and the lack of display brightness became really apparent - I have to run at 5 indoors to see it.
I've been wondering for a while about trying to expand on the information on Joe's site so we can do a 'proper' fix for the display control issue, but that board isn't easy to trace as there's no contrast between tracks and PCB! I agree with Kev, the W1P is most likely a PMBT2222A, that ties up with the SMD codebook (http://www.marsport.org.uk/smd/mainframe.htm), 1P is a generally a -x-2222A device. The Nexperia data sheet page 2 shows the W as a fab. site code (https://assets.nexperia.com/documents/data-sheet/PMBT2222_PMBT2222A.pdf 2F is likely its complement, an -x-2907A. In the OnSemi version (https://www.onsemi.com/pub/Collateral/PZT2907A-D.PDF) page 1 shows the marking for MMBT2907A as 2F. Noritake's site isn't the easiest to navigate, but this Futaba document gives a very detailed explanation of VFD technology: http://www.vwlowen.co.uk/arduino/vfd/VFD-Application-Note.pdf, section 5.1 is particularly interesting. Filament voltage should be maintained at a fixed, optimal level, not used to control brightness, so I do wonder what the circuit in the Boom looks like, I'm not convinced it can be the current of 2A that Joe suggests, that seems excessively high based on the Futaba data and outside of the Ic of the transistors above. Andy. ------------------------------------------------------------------------ ALW's Profile: http://forums.slimdevices.com/member.php?userid=69957 View this thread: http://forums.slimdevices.com/showthread.php?t=111945 _______________________________________________ Boom mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/boom
