Yoshizen's Blog

Small Repair (2)

My friend brought a broken external speaker to our Weekly Meeting

in Greenwich.  Its left channel was working but the condition was not stable.

—– When electronic device was unstable to a mechanical shock,  the cause

may be in a mechanical component such as switch, volume control

otherwise somewhere has a loose connection. 

VR repair(1)83-001

With a detailed observation inside and the check of the resistance value,  

the Volume Control (blue block)  found to be faulty.

—– So,  I removed it from the board and disassembled to see the inside.

On the middle of right photo, you can see the burnt-out volume structure.

VR repair(2)84-001

To check whether rest of the circuit is sound or not,  the best way is to put

fixed value resistor in place of Volume, in this case  20 kΩ  ganged volume was

replaced by 4 x 10 kΩ  resistors which gives a setting somewhere in the middle.

—– As I couldn’t find the identical replacement,  I put an equivalent

Ganged Volume ( they are for each Left and Right channel) instead.  

The repair has done and it worked perfect.   (don’t complain poor look and some

inconveniences = repair was for the function.  As long as the sound is OK, it’s OK

—– to enjoy the quality of sound, out of Philips Amp and the Speaker, while pay

nothing — don’t ask too much.  😀 )  

( After all, repair was also free  =  neither me paying any tuition fee, still I learned

quite amazing idea of Philips’ audio design  = What a fun ! )

[]

Advertisements

2 Responses

Subscribe to comments with RSS.

  1. elenacaravela said, on May 16, 2014 at 18:55

    Way over my head. I admire your expertise.

    • yoshizen said, on May 16, 2014 at 19:29

      I learned from the broken junk. Not from the school.
      = no theory needed. Just do the same. 😀


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: