DM4800 All switch lights stay on after start up including overload leds

[ghook]

Hi ,I have an early version DM4800 which is about 14 years old and on startup today all the switch led's and overload leds remain lit.Everything seems to work ok but obviously is unusable in its current state.Has anyone had this issue happen or know a fix.I tried a diagnostic test and found the (F11 clear Out) button in the Machine Control section was not working.I tried contact spray to no avail.Thanks for any help anyone can give.Geoff from Australia

 

[cmaffia]

Did you try DeOxit? Would a perpetually stuck F11 button cause all lights to stay on? Something else is up

 

[ghook]

Thanks for your reply.I only tried contact cleaner.Like you I think something else is up.I just don't know what it is.

 

[cmaffia]

It's a short somewhere. Not sure it's related to F11 key.

 

[ghook]

Thanks cmaffia,I think I better ring Tascam Australia to seek a repairer who can check it out.

 

[Fiber]

I think your power supply has a problem on one rail, probably ripple that keeps it in a bootloop. These machines are getting quite old so I guess the caps are starting to dry out.

 

[ghook]

Hi All,I’m reopening this post to advise that my F11 key has been repaired but the issue with startup is still making the desk unusable.I have been advised by a repairer that if it’s faulty circuit boards that they are probably no longer available and if they are available that they probably are dearer than buying a second hand desk outright.My question is that are these units too old now to risk buying second hand or am I just unlucky to have mine die. I have the opportunity to buy a second hand desk to replace mine but I would appreciate any comments that people may have regarding the reliability of the units as they get older.Thanks GHook