Can this be fixed or, if not, can it be replicated? - Page 1
Forum section: electronics / beginners

author: thefman
author_rank: Newbie
timestamp: July 03, 2023, 01:47:05 pm
content: Hello,I'm sorry if this is a weird question, I have little to no experience with electronics. I own this wonderful old speakers from Creative. It's a 7.1 system, model Inspire P7800.A few months ago the volume/power(/bass) control started acting up. A little bump on the desk and it would get back to work. The main problem was the that the volume would jump randomly, from very low to very loud. A bump and then it would stay put. Wiggling the power/volume wheel would also fix it, so my intuition tells me that the problem lies there. As you can see in the images, I've opened the box and taken a look inside. Everything looks "fine" to me, but then again, I have not much of an idea what I'm looking at. I've cleaned it with 90% alcohol and checked the cables. There's a tiny bit of rust. I don't see anything too dramatic. Yet, it's fully dead now. Doesn't turn on at all.So, for some background, this cable goes to the subwoofer (circular connector). The subwoofer has input for a few audio cables, and output for a few speakers. Also, the power source goes into the subwoofer. So, everything happens there. The control turns it on and adjusts the volume and bass (with 2 separate wheels, one for power/volume and one for bass).I'm sorry for the wall of text, I'm not really sure how much info is needed.I know I can't do much myself, I don't even have the tools for it. But I'm wondering if there's any hope. Maybe someone can fix it? Is it fixable? Is it possible to recreate it? Is that even a thing?Again, sorry for so much text and thank you in advance for any and all helpEdit: I think the images are not showing, so I attached them too just in case.

author: radiolistener
author_rank: Super Contributor
timestamp: July 03, 2023, 01:56:21 pm
content: yes, it can be fixed and can be replicated. Since there is no MCU with copy-protected firmware, nothing prevent to replicate it.

author: thefman
author_rank: Newbie
timestamp: July 03, 2023, 02:12:33 pm
content: This is great news! Thank you! Any idea what type of business does this?

author: Grandchuck
author_rank: Super Contributor
timestamp: July 03, 2023, 02:50:40 pm
content: Some solder joints look suspicious. Try twisting and tapping and pushing with an insulated tool. It can be resoldered if need be.

author: HwAoRrDk
author_rank: Super Contributor
timestamp: July 03, 2023, 02:58:37 pm
content: Yeah, some of those solder joints look cracked. In particular, the right-hand wheel and the 3.5mm jack on the left.Given that wheel is the power switch, that might explain why it doesn't power on any more.A quick touch-up of all the joints using a soldering iron with some fresh solder may bring it back to life.

author: M0HZH
author_rank: Regular Contributor
timestamp: July 03, 2023, 03:39:29 pm
content: Sounds like the potentiometers are gone, the 5-pin parts under the black rotary dials. Replace those, it's ll be fine.

author: Terry Bites
author_rank: Super Contributor
timestamp: July 03, 2023, 03:50:40 pm
content: The cable and the din connector are the prime suspects and very easily replaced.You could get in there with a small soldering iron and reflow all the joints with a little fresh solder.If you know anyone with a soldering iron and then they probably could fix it.A car mechanic or autoelectrics technician could diagnose and fix this problem, I've no doubt.Do you have a local electronics or radio amateur club?I'm sure if you give a rough idea of your location, one of our German members will offer their assistance.It would be inexpensive and trivial and to reverse engineer.It just screams Quality with a K.

author: mikerj
author_rank: Super Contributor
timestamp: July 03, 2023, 10:19:25 pm
content: There are definitely two and maybe three cracked solder joints on the right hand pot. These could explain all your symptoms, so first port of call is to fix those.

author: Eraldo
author_rank: Regular Contributor
timestamp: July 03, 2023, 10:31:12 pm
content: Yeah the potentiometer is the prime and most obvious suspect and as some others have said your beat bet would be to reflow the solder joints with whatever soldering iron with temperature control you got. If that doesn't fix it, try some wd40 and if that doesn't work either try tighting the screws a bit (not too much or it'll break) and if that too doesn't work then you might try to open the potentiometer altogether and widen the contact pins so it makes better contact and hope for the best. I dontkow if you can get that part off the shelf but if you can and everything else fails, it would be an easy fixGood luck

author: wasedadoc
author_rank: Super Contributor
timestamp: July 03, 2023, 10:45:04 pm
content: Do NOT apply WD40. At best it will not improve matters. At worst it will make things even worse.

author: themadhippy
author_rank: Super Contributor
timestamp: July 03, 2023, 11:06:12 pm
content: Quoteunless its wd40 contact cleaner

author: DavidAlfa
author_rank: Super Contributor
timestamp: July 03, 2023, 11:10:02 pm
content: I own the same, bought it new in 2003!Still behing my 55" Bravia for action moviesIt died once, a zener shorted out, so the internal power supply stopped working, easy fix.I had the same issue as yours, I remember wetting the potentiometers in alcohol and moving them like a maniac to clean them, it never failed again.Check the small rivets holding the pins, sometimes they come loose, easy fix with a bit of solder.

author: SmallCog
author_rank: Frequent Contributor
timestamp: July 04, 2023, 03:27:29 am
content: An option to get those solder joints touched up would be a "repair cafe" if you have any in your local area

author: mengfei
author_rank: Regular Contributor
timestamp: July 04, 2023, 06:16:32 am
content: upon closer inspection it looks like a broken solder, try to re-solder the pot & connector joint