Let me share with you something I stumbled on yesterday..
A friend of mine own a TASCAM DR-2d portable digital audio recorder.
This unit could run out of 2 x AA batteries OR a 5vdc TASCAM original supply.
He had the bad idea to use a 'generic' adjustable
wall wart power supply that was supposely at 4.5vdc hmmmm...
Bad idea.. these suplies mostly comes unregulated.
Too many volts ? bad polarity ? I'll never know.
The result, the blown unit doesn't power up anymore.
Ok. That's the start of the story.
So I opened the unit to find that all the electronics
were on 2 PCB's face to face, completely packed with
VERY TINY surface mount parts on both sides of each boards.
First I suspected a shorted protecting diode right
next to the supply connector so I started looking around
the surrounding parts.. oh man.. microscope job.. then I
decided it would be a good idea to order the service manual
to get the job done faster.
TASCAM answered me the service manual was OUT OF PRINT
but I could order it and get it by mail after a 2-3 weeks delay.
They were not very clear about the cost and the way to pay
for it. Finaly after around 6 emails TASCAM/TEAC California office gently emailed
me a PDF version of the manual for free.
So I was very anxious to check out the schematic and figure out
where the problem could be in the circuitry.
My reading was very short.. The service manual only contained
- a brief list of error messages trouble shooting
(worthless because the unit was dead)
- parts Exploded view
- parts list
- small color prints of pcb's
(both layers on top of each other so not readable)
That's it !
NO SCHEMATICS.
So the only thing that was left to me was to
ask TASCAM the cost of each of the 2 main boards
I cool swap for new ones to get the unit working.
Here is the reply I received:
Main board#1 $250.00US
Main board#2 $140.00US
Plus shipping.
FYI a brand new unit in its box sells today for around $189.00US !!!
So here is my frustration explained:
For short, in the 70's in Canada (were I live) there was 2 types of electronics courses:
- 1 year short course aimed for small home and cars appliances repairs
- 3 years complete course (analog, digital, logic, software, development, etc..)
this course was VERY CLOSE to the engineer's university course
That's the one I chose to pickup.
In the past 40 years (beside the elect. development I did)
I always put my hands on repairable electronics.
The stuff were made using tubes, transistors, IC's, etc..
The degree I got out of my course brought me knowledge
to analyse and fix blown circuits. I earned experience out
of all my findings.
Now I'm facing a world of BUY, USE THEN THROW AWAY (AFTER AROUND 5-6 YEARS OF USE).
We came up to a point where a qualified tech is almost
worthless. I talked to a repair store near Quebec City maybe they
would have the TASCAM service manual on hand and the repairs man
said to me:
We almost stopped using service manuals on new stuff..
The techs know what problem comes often on the electronic
stuff we sell and they mostly replace complete boards
without bothering what the blown part(s) were !!!!!
Conclusion:
Now, new stuff can be repaired (when not disposed)
by 'REPLACE BOARDs' techs with small knowledge of electronics.
In the next future, only:
-repair shops that fix old repairable stuff (radios, music amps, keyboards, etc..)
-R&D & electronic design houses
will be the only place left for us techs who
like to express our WIDE knowledge in our daily jobs.
Just my 3 cents !!
J-Pierre
Quebec City, Canada
A friend of mine own a TASCAM DR-2d portable digital audio recorder.
This unit could run out of 2 x AA batteries OR a 5vdc TASCAM original supply.
He had the bad idea to use a 'generic' adjustable
wall wart power supply that was supposely at 4.5vdc hmmmm...
Bad idea.. these suplies mostly comes unregulated.
Too many volts ? bad polarity ? I'll never know.
The result, the blown unit doesn't power up anymore.
Ok. That's the start of the story.
So I opened the unit to find that all the electronics
were on 2 PCB's face to face, completely packed with
VERY TINY surface mount parts on both sides of each boards.
First I suspected a shorted protecting diode right
next to the supply connector so I started looking around
the surrounding parts.. oh man.. microscope job.. then I
decided it would be a good idea to order the service manual
to get the job done faster.
TASCAM answered me the service manual was OUT OF PRINT
but I could order it and get it by mail after a 2-3 weeks delay.
They were not very clear about the cost and the way to pay
for it. Finaly after around 6 emails TASCAM/TEAC California office gently emailed
me a PDF version of the manual for free.
So I was very anxious to check out the schematic and figure out
where the problem could be in the circuitry.
My reading was very short.. The service manual only contained
- a brief list of error messages trouble shooting
(worthless because the unit was dead)
- parts Exploded view
- parts list
- small color prints of pcb's
(both layers on top of each other so not readable)
That's it !
NO SCHEMATICS.
So the only thing that was left to me was to
ask TASCAM the cost of each of the 2 main boards
I cool swap for new ones to get the unit working.
Here is the reply I received:
Main board#1 $250.00US
Main board#2 $140.00US
Plus shipping.
FYI a brand new unit in its box sells today for around $189.00US !!!
So here is my frustration explained:
For short, in the 70's in Canada (were I live) there was 2 types of electronics courses:
- 1 year short course aimed for small home and cars appliances repairs
- 3 years complete course (analog, digital, logic, software, development, etc..)
this course was VERY CLOSE to the engineer's university course
That's the one I chose to pickup.
In the past 40 years (beside the elect. development I did)
I always put my hands on repairable electronics.
The stuff were made using tubes, transistors, IC's, etc..
The degree I got out of my course brought me knowledge
to analyse and fix blown circuits. I earned experience out
of all my findings.
Now I'm facing a world of BUY, USE THEN THROW AWAY (AFTER AROUND 5-6 YEARS OF USE).
We came up to a point where a qualified tech is almost
worthless. I talked to a repair store near Quebec City maybe they
would have the TASCAM service manual on hand and the repairs man
said to me:
We almost stopped using service manuals on new stuff..
The techs know what problem comes often on the electronic
stuff we sell and they mostly replace complete boards
without bothering what the blown part(s) were !!!!!
Conclusion:
Now, new stuff can be repaired (when not disposed)
by 'REPLACE BOARDs' techs with small knowledge of electronics.
In the next future, only:
-repair shops that fix old repairable stuff (radios, music amps, keyboards, etc..)
-R&D & electronic design houses
will be the only place left for us techs who
like to express our WIDE knowledge in our daily jobs.
Just my 3 cents !!
J-Pierre
Quebec City, Canada