I'm trying to repair a Makita DMR110N for a friend. It originally did not turn on. It was dropped from a reasonable height and failed. When I got it apart, a transistor had blown up. The same transistor as had blown in this link:
https://maker.pro/forums/threads/replace-blown-component-makita-radio-dmr104.293953/
Which is a 2SB1143.

I swapped this out for a new one, and the device now powers up and operates correctly visually (all buttons work etc) however there's absolutely no sound whatsoever so I'm guessing something downstream has died. You can hear that the speakers seem to be receiving a small amount power as there's a very very faint amount of noise which is common with powered radios, amps etc, but no matter whether I use aux, or dab radio, or FM, there's absolutely no sound whatsoever.

I've attached some images that show the component which I've replaced and also the rest of the PCB's. Are there any known failure points? I've reflowed the ET2314 which is a digital audio input processor and also what appears to be the amp chips solder connections, but this has made no difference as of yet.

Any suggestions? I was thinking of replacing the ET2314 but it feels like I'm just guessing at this point. How would I best diagnose it?

I've uploaded some photos:

This is the transistor I've replaced, the same as the one identified in the other thread.

Reflowed the below, the ET2314 and the Amp chip but to no avail...

 

Hi,
With the unit powered up, you could go all over it with a stiffish clean dry paint brush.
It may spring to life and give you a clue to the problem area.
Good luck.............

 

I'm trying to repair a Makita DMR110N for a friend. It originally did not turn on. It was dropped from a reasonable height and failed. When I got it apart, a transistor had blown up. The same transistor as had blown in this link:
https://maker.pro/forums/threads/replace-blown-component-makita-radio-dmr104.293953/
Which is a 2SB1143.

I swapped this out for a new one, and the device now powers up and operates correctly visually (all buttons work etc) however there's absolutely no sound whatsoever so I'm guessing something downstream has died. You can hear that the speakers seem to be receiving a small amount power as there's a very very faint amount of noise which is common with powered radios, amps etc, but no matter whether I use aux, or dab radio, or FM, there's absolutely no sound whatsoever.

I've attached some images that show the component which I've replaced and also the rest of the PCB's. Are there any known failure points? I've reflowed the ET2314 which is a digital audio input processor and also what appears to be the amp chips solder connections, but this has made no difference as of yet.

Any suggestions? I was thinking of replacing the ET2314 but it feels like I'm just guessing at this point. How would I best diagnose it?

I've uploaded some photos:

This is the transistor I've replaced, the same as the one identified in the other thread.

Reflowed the below, the ET2314 and the Amp chip but to no avail...

I dabble a little in Roberts radio and I will give my little knowledge for what it’s worth.
I have had a couple of sound issues which was down to the headphone jack. Try plugging in some headphones and see if you get sound coming from them. If so then the headphone jack will need either cleaning or replacing.
The audio chip could be at fault too or components around it, like caps or resistors, just measure around the chip with a DMM, also try the IPA trick on suspect component to see if they are getting hot.
Double check the speaker connection, it may have become detached with the fall.
I know nothing about these particular radios so I maybe talking crap but it’s worth checking.

Good luck

 

I'm trying to repair a Makita DMR110N for a friend. It originally did not turn on. It was dropped from a reasonable height and failed. When I got it apart, a transistor had blown up. The same transistor as had blown in this link:
https://maker.pro/forums/threads/replace-blown-component-makita-radio-dmr104.293953/
Which is a 2SB1143.

I swapped this out for a new one, and the device now powers up and operates correctly visually (all buttons work etc) however there's absolutely no sound whatsoever so I'm guessing something downstream has died. You can hear that the speakers seem to be receiving a small amount power as there's a very very faint amount of noise which is common with powered radios, amps etc, but no matter whether I use aux, or dab radio, or FM, there's absolutely no sound whatsoever.

I've attached some images that show the component which I've replaced and also the rest of the PCB's. Are there any known failure points? I've reflowed the ET2314 which is a digital audio input processor and also what appears to be the amp chips solder connections, but this has made no difference as of yet.

Any suggestions? I was thinking of replacing the ET2314 but it feels like I'm just guessing at this point. How would I best diagnose it?

I've uploaded some photos:

This is the transistor I've replaced, the same as the one identified in the other thread.

Reflowed the below, the ET2314 and the Amp chip but to no avail...

@skezza did you ever find a solution for this (I realise its a bit of a thread revival) but my Makita 110N DAB + has the same issue yours did after you managed to power it up? Mine has never been dropped but the sound just stopped. Any info would be great.

 

hi deacs,
Welcome to AAC.
skezza has not logged on since Aug 2024, suggest you start your own new thread.

Moderation

 

Thanks for the welcome and login stats @ericgibbs, much appreciated.
I figured it was along shot. Will do.