Lasonic 931s..... what's the deal?

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blu_fuz

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I'm having a hell of a time trying to pull the guts out of a 2nd edition 931. Every wire is soldered, stacked circuit boards, and a tangled mess of wires criss-crossing all over the decks and behind the left woofer.

Is there some trick to getting this all out in one piece or are there certain solder spots I need to disconnect?


I'm frustrated and done for now, but for such a simple box Lasonic made this way harder that it needs to be.......
 

blu_fuz

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So you pretty much need to de-solder EVERYTHING!? Hahaha. What do you disconnect to pull it all out? I kind of want to add a ton of connectors while I have it apart.
 

baddboybill

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If you disconnect speakers you might be able to take everything out with 4 hands. You and your wife's ;-). 2 boards 2 decks. But you also need to unscrew the LEDs and I'm not 100% sure how EQ is if its on separate board :hmmm: but there is a way to do it ;-)
 

Superduper

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It's a real PITA. There is no chassis, so every board stands on it's own. Worse, each board (or module) has wires that goes to more than one other module. It's more than just the speakers, it's everything. Forget about adding connectors.... there will be about 40 of them if you do, and adding connectors to the shielded signal cables merely introduces noise. Also, the issue is more than just connectors, it's that there is no clear systematic or intuitive way they all mesh together. Unlike a whole cluster of wires in one spot where you can add a 3 or 6 or 8 pin connector, they are just interspersed all over.

Best thing to do is just document where everything goes best you can because if you forget.............. :grim:
In fact, if you knew where everything goes like the back of your hand, the soldering part just might just be the easiest part of assembly/disassembly.

Frankly, in my mind, it's a terrible design. Unlike JVC's, a lot of Sanyos have their boards tethered with everything soldered together. But at least they routed their wires neatly so if you unsoldered one board, you can tell which wires goes to that particular board by the bundling and you can sort of figure out which goes where on the board simply by the wire lengths. On the lasonic, it seems like there is NO wire routing system and they just soldered wires from spot to spot by taking the shortest path.
 

Cpl-Chronic

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Superduper said:
It's a real PITA. There is no chassis, so every board stands on it's own. Worse, each board (or module) has wires that goes to more than one other module. It's more than just the speakers, it's everything. Forget about adding connectors.... there will be about 40 of them if you do, and adding connectors to the shielded signal cables merely introduces noise. Also, the issue is more than just connectors, it's that there is no clear systematic or intuitive way they all mesh together. Unlike a whole cluster of wires in one spot where you can add a 3 or 6 or 8 pin connector, they are just interspersed all over.

Best thing to do is just document where everything goes best you can because if you forget.............. :grim:
In fact, if you knew where everything goes like the back of your hand, the soldering part just might just be the easiest part of assembly/disassembly.

Frankly, in my mind, it's a terrible design. Unlike JVC's, a lot of Sanyos have their boards tethered with everything soldered together. But at least they routed their wires neatly so if you unsoldered one board, you can tell which wires goes to that particular board by the bundling and you can sort of figure out which goes where on the board simply by the wire lengths. On the lasonic, it seems like there is NO wire routing system and they just soldered wires from spot to spot by taking the shortest path.
Hmmm...sounds like Lasonics are cheap POS s#!^. Why do so many people like them? If I opened the back of a boombox & it was a total shizo mess inside, I'd probably gut it for parts & get rid of it.. I hate crappy electronics that are meant to be thrown away when they break. But hey, some people LOVE lasoinics. I guess some models sound good, with plenty of controls & features. I've never owned 1 myself & probably won't after reading Super's take on it. :thumbsdown:
 

blu_fuz

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I was actually able to get all the parts out, still tethered together by myself. I kind of gave it all a bear hug and set it off to the side :lol: :dunce: .


It's crazy! :lol: :-O


I agree Bill, with 4 hands it would be no problem to grab all the heaviest bits and let the boards lay on them as you lift out the guts. :surf:

I agree Norm, holy crap that would be a ton of connectors and a serious waste of time! :thumbsdown:


They really did just route wires the shortest path possible. You can't even lift the main board up and out of the way without messing with 5 other things and removing the screws that hold them in place too :thumbsdown: :nonono: . By the time you do all that, you mind as well take the rest of the screws out and pull everything :-/ .
 

stynger007

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blu_fuz said:
I'm having a hell of a time trying to pull the guts out of a 2nd edition 931. Every wire is soldered, stacked circuit boards, and a tangled mess of wires criss-crossing all over the decks and behind the left woofer.

Is there some trick to getting this all out in one piece or are there certain solder spots I need to disconnect?


I'm frustrated and done for now, but for such a simple box Lasonic made this way harder that it needs to be.......
Yes, these 931`s are known for cold solder joints too- the wires are very brittle and snap off almost by the touch- as another poster said they are a bear to get apart..if you`re needing to remove entire boards, a piece of masking tape labeled with a color dot on a wire removed ,and on the circuit board works well :-)
 

baddboybill

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I agree the design sucks and luckily Lasonic changed it in the I931 which now has plugs from board to board :thumbsup: I can just imagine the technicians putting these together in the day. I bet most of them had no hair left :lol: :lol:
 

Lasonic TRC-920

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The Aiwa I just finished was the same way, just had a chassis, but was layered without connectors by soldering everything together AFTER the PC Boards were in.

I do plan on getting a 931 down the line.

As crazy as it is....it might be time to open the box, take one picture, upload it to the computer PAGE 1. Remove ONE WIRE, take a picture, up load it to the computer, import into photoshop, highlight where the wire went, where it was soldered and what color it was PAGE TWO and so on. It SUCKS, but it could then be printed or uploaded.

I have to say, there is a similar guide to taking apart the VZ2000 that is on this site and I could not have done that radio with out it :no: Thank GOD someone took the time to create it. If someone want's to donate a 931 to the cause I will handle it....For The Good of the site of course :-D :yes: :-P

If I get a 931 down the line, I will see if I can do this. In the end, it still may not help, because there are 3 generations made by different factories. BTW, the 920 is the same way.

Good Luck Fuz,
 

baddboybill

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Lasonic TRC-920 said:
The Aiwa I just finished was the same way, just had a chassis, but was layered without connectors by soldering everything together AFTER the PC Boards were in.

I do plan on getting a 931 down the line.

As crazy as it is....it might be time to open the box, take one picture, upload it to the computer PAGE 1. Remove ONE WIRE, take a picture, up load it to the computer, import into photoshop, highlight where the wire went, where it was soldered and what color it was PAGE TWO and so on. It SUCKS, but it could then be printed or uploaded.

I have to say, there is a similar guide to taking apart the VZ2000 that is on this site and I could not have done that radio with out it :no: Thank GOD someone took the time to create it. If someone want's to donate a 931 to the cause I will handle it....For The Good of the site of course :-D :yes: :-P

If I get a 931 down the line, I will see if I can do this. In the end, it still may not help, because there are 3 generations made by different factories. BTW, the 920 is the same way.

Good Luck Fuz,
Actually all Lasonics have hard wired boards and no plugs except I931 ;-)
 

blu_fuz

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You are right bill. Now looking back at when I was swapping guts of 975's, everything was all tangled together :thumbsdown: . It was actually easier though because there was more slack in the wires so you could loosen, flip, and stack the boards nice to remove everything.



Anywho, my Black Friday brown label early 2nd edition 931 I have had for a couple years is back together and restored :surf: . I honestly didn't think every wire connection was going to be ok to the board. All that moving around I figured I would have a bad solder joint somewhere, but I got lucky :yes: .



If you are thinking about working on a 931, be ready :lol: :dunce: . I don't plan on doing that again anytime soon :thumbsdown: .



 

blu_fuz

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That was about 1/2 way through, I just needed to give my back a rest from hunching over the boombox for so long and figured I would snap a quick picture :lol:



:sick: :blink: :dunce: :bang: :drunk: :jason:
 

DJBREEZY

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I'm attempting to fix the stereo/mono and loundess switches that are loose on my 931(1st edition). I wanted to know how to get the eq/function switches board loose? I have all the screws out, the eq side will pull up but the other side feels like it's still being tied down by something? wondering how you got yours loose?? :bang: :bang:

Thanks!
 

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