Need schematic for Bose Wave Music System AWRCC1 pcb 272146-001

[JCSTOKES]

My Bose Wave Music System (with CD) AWR11C won't power up. I am unable to find anything on this model. Any help appreciated.

I suspect the problem is on the power/audio amp board 272146-001.



Thanks Gary W5UUO

 

[Martaine2005]

Hi Gary,
The schematic seems to be very well hidden. I will keep looking though.
I presume you have opened it to have the board numbers.
Not powering up will certainly be the power supply. I also presume you have checked on-board fuses?
A little more information will help.
What have you checked? With what and how for example.
Any lights? Any noises?
OR plain dead?

Martin

 

[JCSTOKES]

Martin ,

Thanks so much for the reply.. I have been a ham for 50 years and really enjoy fixing tube radios.. but I am no pro..really just a hacker..

Yes, I have it open and have found the fuses, power transformer, and 15V supply are ok.. I have tested all the above board large 3 legged ICs, the diodes, and the large filter caps.. they are all ok.. Then I started looking for the 5V regulator and got lost.

Looking at the other versions of Bose Wave they talk about Q4 being the 5V regulator.. but there is no Q4 on this pcb... and many of the 3 legged SMA chips have no silkscreen designation..

So right now I am trying to reverse engineer and with my 71 year old eyes is it a hair frustrating.. HAHAHA..

If I just knew where the 5V regular was on the board it would be a huge help.. any marking on the SMA chip would also help..

I started ohm meter testing the three legged chips under the board and found one that seems open.. I need to figure out what is is and replace it...

So there's the status..

Any ideas?

 

[Martaine2005]

I have been a ham for 50 years

You could probably do well in fly swats with your experience then .

Hi Gary, Yes the smd components are rather frustrating. The reference designators seem to be non existent.
They do however have a code on the body. Not that the code can always be found either.
But I find a good magnifying glass really helps.
Look up TO623 or sot-223 packages. You will understand what I mean.

Martin

 

[JCSTOKES]

Thanks Martin,

I did find this that lets you translate the sma codes for actual transistor types.
.http://www.marsport.org.uk/smd/mainframe.htm

So maybe there is hope .. Again thanks for the responding and the help...

Gary