Repair of a Bowers & Wilkins A7 Wireless Speaker
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- Опубликовано: 8 сен 2024
- This B&W A7 was completely dead and this seems to be a common report with these units. There is some adventure in taking it apart but with some gentle persuasion and a hammer we get there and confirm there is a power supply problem. A bit more adventure to get the power supply out and its clear that something has gone drastically wrong. Investigation shows that the power amp supply section has failed. After getting some replacement parts and chasing my tail for a while the unit is re-assembled and is musical once more.
This power supply module and fault seem to be common across a number of B&W units.
I have to say well done, it’s refreshing that you take on jobs like these rather than just bin it in todays built in obsolescence culture
Hi there, Do you have a full list of the parts your removed? So easier for me to order in one go. Thanks.
Its an expensive product that does offer high quality sound but its cheaply made, plastic cabinet, messy inners and this power supply fuse and capaciter problem is common with the bowers and wilkins zeppelin line also.
Awesome video
Thanks for this great and helpful video!
Could you explain which values had the resistors you used for your test setup? I have an broken A7 Speaker too, that dont want to turn on, and so would like to measure the powersupply, because i am not sure if its faulty, because the fuse and the mosfets and the triac seem to be okay.
This isn't critical, I had 50 ohms on the 5v and 100 ohms on the +-18v
@@myalbatech Thank you very much! :-)
what is the source of the music?
Thank you for this tutorial. Where were you able to get the replacement parts from?
Mouser Electronics
Really useful video. Thanks! Can you share details of the mosfet controller / device or a replacement that you used? (7387 XCFJK - U4 on the board). I think mine is blown so need to replace and I can't find details for it anywhere.
It's FAN7387
@@myalbatech Thanks!
I have one, but I have an alternating voltage on the smd.. and not continuous, do you think the problem comes from capacitors or other things?? Because I'm looking but I can't find anything
I explain to you my card makes a kind of click when I power it, and when I remove the 3 capacitors that are in parallel, I no longer have the click but I still don't have 19 V at the pines. I searched everywhere but I didn't find anything and I don't really see what it could be
But I have 5 volts on the other pins but I don’t know what values I need to have on each pins
Great video myalbatech! Very helpful for me.
I have solved the power board issue, but I now still have an issue with the WiFi module. I am sure that it is the WiFi module, because I have a WiFi module of another A7. And I swapped it for testing. With the swapped WiFi module the A7 works perfect.
Someone mentioned to me to replace the capacitor on the WiFi module. I did but it did not help.
Question
Do you have any clue?
Haven't dealt with the WiFi module so far I'm afraid.
@@myalbatech Do you know anyone, who might have experience?
Im afraid not@@KolfMAKER
Reputable company , sells you a fairly expensive product. You think the work would be top notch
Looking at the power supply. Excessive amount
Of glue , used to secure the capacitors and another
Puddle of soldering that connects the cable to the
Power supply. There wasn’t any insulation to speak
Of , reminds of Bose . But there equipment sucks