Hello Kitty boom box volume

[wolf9545]

I found a fairly new (September 2008) Hello Kitty boom box; has the option to play cd's and cassettes. It works fine, powers up, etc. but the only problem I am having is the volume knob does not adjust the volume. When the unit is on it basically is set to "very loud". The knob does turn and I can see the POT turning. When I turn the knob I don't hear the volume change; I also do not hear any pops or cracks to indicate a dirty POT. I did spray some electrical contact cleaner inside the POT but that did not seem to help at all. Any suggestions?

 

[KJ6EAD]

You're going to have to open the unit up and test the pot with a meter. Of course, while you're in there you'll be looking for cracks in the solder, etc.

 

[duffy]

One side of the volume pot is usually connected to ground, a break there would cause the problem.

 

[wolf9545]

Sorry about not replying. I have been busy with work and other things. I'll try to get some pictures of the board and see if I can spot any bad solder joints.

 

[wolf9545]

Ok, I re-opened up the boom box and took a look at the pot. After taking my soldering iron and re-heating up the solder on the connections it seemed to help somewhat. Sometimes the volume adjustment will work fine and sometimes it goes back to just being loud. It mostly seems to happen if you tilt the volume knob up or down instead of rotating it. I don't know if there still is some breaks in the solder or if the pot itself is cracked inside.

 

[KJ6EAD]

It seems that the wiper is bent and is intermittently losing contact with the resistive element or it's connection to it's mounting lug. Replace the pot.