Lasonic 931i won't power up.

[tallpaul]

Gents,

Is it worth getting involved with this unit as its not powering up using mains or batteries ?? Its for sale on flea bay. Condition looks decent, apparently just requires an aerial. TIA

Paul.

 

[BoomboxLover48]

I would buy it and fix. It could be a simple problem in most cases.

 

[Superduper]

It's risky. That unit does not power up like the old school analog boomboxes. It requires a digital momentary signal to power up. If you have a problem with regular electronics, this unit will require an even greater skill to troubleshoot and there's no schematics that I'm aware of.

 

[floyd]

These have an ac/DC switch that might be in the wrong position, when they tested I , also on some occasions the springs/ contacts inside the battery compartment are not in the right spot to touch the batteries , I've had this problem before.

 

[tallpaul]

Mmm, great info as usual thanks. Would it have an internal fuse and if it's been overpowered with 240v would it have the usual burnt smell inside the case?

 

[floyd]

Mmm, great info as usual thanks. Would it have an internal fuse and if it's been overpowered with 240v would it have the usual burnt smell inside the case?

I've never seen an internal fuse in a lasonic but the wrong voltage setting could burn it up if it's set to 110 and plugged into 220 volts.

 

[tallpaul]

I think I'll take a look before bidding on it. Thank you for your help guys 👍

 

[baddboybill]

If Lasonic was still in business you could get parts but I think they no longer sell parts. These are built like new electronics which components are more difficult to test and replace. You pretty much replace the whole board when something is wrong

 

[Superduper]

If Lasonic was still in business you could get parts but I think they no longer sell parts. These are built like new electronics which components are more difficult to test and replace. You pretty much replace the whole board when something is wrong

It's why I say it could be risky. There's 2 methods of failure. If it's a AC/DC switch problem or other issue where power is not getting to the mainboard, it obviously won't power up. But the other scenario is where the mainboard DOES get power, but still won't power up, that will be problematic. Many owners have noticed that if you leave batteries in the boombox, they go dead pretty quickly, even when not being used. The reason is that the mainboard constantly receives power. The power button you press is merely a momentary switch that alerts the mainboard that you want to power up. In other words, the mainboard is constantly powered and monitors the power switch for a depression. The mainboard then electronically communicates this and powers up the boombox. Ergo, if the problem is with the logic circuits that powers up the radio, then Houston, we have a problem and not one that is as simple as figuring out why no power is getting to the board. Without a schematic, I personally probably wouldn't touch it unless it was dirt cheap but that's just me. You could luck out.

 

[floyd]

I can't remember is these have the 12 volt socket on the back or not but if so it could be another way to apply power but like norm said its a gamble because these are nothing like the old lasonics inside.

 

[Styleking]

I agree with Norm, if it was dirt cheap you could possibly sell parts to recoup your investment. The value of these boxes hasn't been trending up.

 

[tallpaul]

Unfortunately it's not dirt cheap but fortunately you guys have my back!!

I will let this box pass me by.

Once again thank you all for your replies....

 

[Transistorized]

Yeah. Superduper is correct. These newer style boxes are more computer than solid state. Since its not powering up with either source, there are only a few simple serviceable options (power supply, PS to board wired connection, DC power port, power button) before it quickly gets to the not worth it area. Not to say a qualified tech couldn't check for bad caps, resistor, diode or traces however, if the fault takes you to a failed IC your sunk.