Freezing and ‘dying’ front panels on DA78HR

There is a socketed com bus I/C mounted vertically on the Key pcb. It manages signals of key press, shift key status, and lights the appropriate LED’s on the front panel. When it starts to lose pin contacts the transport keys may not function, other keys may not, and worst case, the panel goes dark. The deck, if rolling/recording, will remain in its’ last good status (play, record, etc.) until the end of tape. If the deck is moved this chip will need to be reseated periodically. Some customer’s report this happening once every few days without even moving the unit. The fix requires removing the front panel, and reseating the I/C chip.

FrontU1 is more or less behind/beside the LOC1 key. It is about 1/2 inch square and is the only socketed chip on the KEY pcb mother board. Remove the rack ears (2 screws each side), remove the top cover to access the remaining front panel screws; remove 3 top and 2 bottom screws to then pull the front/control panel evenly toward you. Pry it a little looser then press as evenly as possible to reseat. The front panel needs some patient jiggling to align the LED’s and switch stems, but it will become second nature with practice.

If you are uncomfortable with this process, or reseating the chip does not help, please contact Sweetwater or Tascam’s Technical Support departments.

Knowledge Base