Lasonic i931 help needed

Status
Not open for further replies.
Northerner

Northerner

Boomus Fidelis
So I somehow managed to find a Lasonic in the UK and for very little money! It was listed as not working but actually it works well on all inputs apart from radio. On fm it has problems finding the stations and then when it does they don't really stay tuned in. Had a look inside and found what my good friend John/Beosystem tells me is a socketed transistor that has somehow got damaged. It's lost the cover so I don't know its type so I can't order a replacement. Can't find a service manual so I'm hoping a kind member who has one would open theirs and get the details of the knackered one for me...please! :-)

image.jpg
image.jpg
 
Northerner

Northerner

Boomus Fidelis
Awesome! Thanks mate. It's the board in between the speakers, just need the back taking off to see it. Really appreciate it :-)
 
Michiel

Michiel

Member (SA)
Beosystem10

Beosystem10

Member (SA)
Si, sorry about that, the QA on the board obviously applies to the printed transistor, the tiny one that looks more like I should expect a modern one to look! Damn, that was some senior moment there but of course MIchiel is absolutely spot on. The + and - markings at either end really should have given the game away, I did wonder why I couldn't see the E, C and B that I was expecting.
By way of punishment to myself for being so dense; I shall send you a suitable cap for no money, PM the address as I can't find it in my phone's navigation list and please, keep the John abuse to a minimum as I feel dumb enough already for mistaking that cap for a T07-style transistor enclosure! :blush: I could use the excuse that I'm too used to seeing 1960s and '70s gear but that wouldn't be a good idea, just in case the guy whose Panasonic music centre I'm fixing tomorrow reads this.

:bang: :bang: :bang: :bang: :bang: :bang: :bang: :bang: :bang: << doing that for real right now...
 
baddboybill

baddboybill

Boomus Fidelis
Honestly it's probably cheaper and easier to try and order whole board from Lasonic. ;-)


Sent from my iPad using Tapatalk
 
Northerner

Northerner

Boomus Fidelis
Beosystem10 said:
Si, sorry about that, the QA on the board obviously applies to the printed transistor, the tiny one that looks more like I should expect a modern one to look! Damn, that was some senior moment there but of course MIchiel is absolutely spot on. The + and - markings at either end really should have given the game away, I did wonder why I couldn't see the E, C and B that I was expecting.
By way of punishment to myself for being so dense; I shall send you a suitable cap for no money, PM the address as I can't find it in my phone's navigation list and please, keep the John abuse to a minimum as I feel dumb enough already for mistaking that cap for a T07-style transistor enclosure! :blush: I could use the excuse that I'm too used to seeing 1960s and '70s gear but that wouldn't be a good idea, just in case the guy whose Panasonic music centre I'm fixing tomorrow reads this.

:bang: :bang: :bang: :bang: :bang: :bang: :bang: :bang: :bang: << doing that for real right now...
Click to expand...
Oops sorry for outing the mistake!...your consolation is that I havent a clue and never would've known lol :-) To be fair its a pretty small and blurry phone pic!

Address being pm'd and thank you so much John, I appreciate your help mate.

And Dave if you could still check yours mate just so we know it's the right one then that would be fab, cheers :-)
 
Northerner

Northerner

Boomus Fidelis
baddboybill said:
Honestly it's probably cheaper and easier to try and order whole board from Lasonic. ;-)


Sent from my iPad using Tapatalk
Click to expand...
I couldn't bring myself to spend more on replacement parts than the £15 I spent buying the whole box lol :-)
 
Beosystem10

Beosystem10

Member (SA)
Northerner said:
Oops sorry for outing the mistake!...your consolation is that I havent a clue and never would've known lol :-) To be fair its a pretty small and blurry phone pic!

Address being pm'd and thank you so much John, I appreciate your help mate.

And Dave if you could still check yours mate just so we know it's the right one then that would be fab, cheers :-)
Click to expand...
That would have been no consolation to me, not when I made a fundamental error that one of my 1st years would have been tarred and feathered for making, though quite why the part that actually is the transistor is annotated QA2 when it's clearly one of these newfangled printed ones and not the T07 socketed type after all is beyond me, that should strictly speaking read simply Q2 or T2.
Then along comes someone and uses a T07 can to disguise an electrolytic cap and my confusion is consolidated in the most embarrassing way!

Northerner said:
I couldn't bring myself to spend more on replacement parts than the £15 I spent buying the whole box lol :-)
Click to expand...
:lol:
One new 100uF electrolytic cap - 25WV as I don't have a radial at 16WV, but the working voltage isn't a problem as long as it's not under the original value - will be winging its way to the People's Republic of Yorkshire asap.
Here 'tis:
15375474421_e93131bec9_h.jpg


Just a thought here, Si; I would tend to replace all of the electrolytics in the same region of the board if I'd found one that had died like that, so if you want another however many of these, just give a shout and I'll send them. Don't worry about the slightly differing form factor of the can, there's no need to go for one of those fancy yet clearly not reliable ones, this one will work at least as well given that these cheaply made modern 'lytics always die prematurely. I've lost count of the number of blown ones I get to see in DVD players that were guaranteed for one year and have little dents in their cabinet lids on the 366th day! Though at least most manufacturers use caps that look like caps and annotate their boards clearly. OK, letting my shame go now.. ;-)
 
Michiel

Michiel

Member (SA)
Lol, dont worry John. I recognised that it used to be a electrolytic cap by all the filthy debris it left after the explosion..:) I hope it solves Si's radio problem btw. I suspect we are looking to the amp board. Seeing that fat cooled IC close to the destroyed cap.... But it needs to be fixed anyway :)
 
Beosystem10

Beosystem10

Member (SA)
Right then, one cap in envelope, your address on envelope, all I have to do is 1) remember to put envelope in car when I go out in the morning and 2) make sure to shove it into a pillar box rather than leaving it in the glove hole and carrying it all the way home again which given my current form isn't outwith the realms of possibility! ;-)

I might even put a stamp on there too...
 
Northerner

Northerner

Boomus Fidelis
Lol...I have a habit of carrying letters around for weeks before I post them...I do the same with cheques, they sit in my wallet for ages before I remember to do anything with it, even when I need the money!

Thanks John, I'll let you know how the repair goes :-)
 
im_alan_partridge

im_alan_partridge

Member (SA)
Hey Si, sorry ive not got that info for you today mate ive been taking advantage of the good weather and getting a few things done.

I will get it done after work tomorrow :yes:
 
Northerner

Northerner

Boomus Fidelis
im_alan_partridge said:
Hey Si, sorry ive not got that info for you today mate ive been taking advantage of the good weather and getting a few things done.

I will get it done after work tomorrow :yes:
Click to expand...
No problems Dave, don't blame you for making the most of the sunshine, I did the same, dog walk then pub lunch...nice! :-)

Just grateful you're willing to check it out...I'd like the reassurance of knowing the one John is sending me is the right one...so thanks mate :-)
 
Beosystem10

Beosystem10

Member (SA)
Good thinking, I suspect it ought to be another of the same value but will wait on Dave's verdict so that I can send something different if it's not a 100μF after all. Check the WV too please, it's very unlikely to be higher but best we know that just in case.
 
Beosystem10

Beosystem10

Member (SA)
:thumbsup: I should just have sent it when I was out & about, yes, that middle one from the three is a 100μF too, in fact the only other one in the same size can looks to be a 47μF and the other, smaller ones are of much lower values.


Si, expect that cap in the post later in the week.
 
Northerner

Northerner

Boomus Fidelis
That's brilliant Dave!...now we know it's definitely the right one...thanks a lot for your trouble mate :-)

And John you're a true gent, thanks :-)
 
Status
Not open for further replies.
Top Bottom