TRC-920 won't play with Batteries

[BassHead]

I cleaned the springs / contacts. This unit has a permanent power supply cable coming from the back of the box, so it doesn't have that small battery shut-off button which units that have a removable power supply cord do. I suppose this is the reason for the AC/DC switch? I've tried the batteries with switch on DC (and even AC), and no luck.

The wiring looks to be fine, and I traced the routing, which matches photos of other 920s I've seen online.

Does anyone have any advice?

 

[docs]

To be sure, you can use a digital multi meter on continuity test with a probe at one end and one at the other to ensure there is continuity. This is always a good place to start because it either shows the fault up immediately or quickly eliminates it so you can move forward with focusing on the next area.

 

[Reli]

Dirty AC/DC switch?

 

[Transistorized]

That last picture I see the barrel plug DC adapter connection. Almost 100% sure that the contacts on that are dirty. With the switch slid to DC if a wall adapter is plugged in or car cigarette power adapter, it terminates power from the batteries when that side leaf inside that barrel plug adapter pushes outward to make room for the barrel plug. When it does this it kills power from the battery leading to that adapter and uses the wall adapter power instead.

My advice. Spray Deoxit in that barrel plug. Insert a proper sized (non powered) barrel adapter plug in there to work the contact leaf switch. Push the adapter plug in and out a few times to help clean it. Then see if it doesn't come to life with batteries after that.

It could be the DC switch but again, I have run into so many radios that the adapter plug terminals were dirty and wouldn't allow voltage to pass it to feed the radio.

 

[BassHead]

Thanks guys. I will clean the switch and break out the multimeter!

I didn't think about cleaning the switch and it does look dirty. It's something that should have come to mind, since all the pots required a good cleaning.....

That last picture I see the barrel plug DC adapter connection. Almost 100% sure that the contacts on that are dirty. When an adapter is plugged in it terminates power from the batteries and uses the wall adapter power instead

THANKS! Good point...

 

[BassHead]

Thank you. Cleaned the switch and DC connection and I got her running on Batteries. Yee!

I realized that the two bottom tabs to my battery cover came smashed with much of the delivery. I collected all the broken plastic pieces but was unable to find a match (for a JB Weld job). Finding a spare shouldn't be too difficult find....but parts for the 920 aren't as ubiquitous as the 931. Does anyone know if the battery cover works with other Lasonics? I would offer $ is anyone has a spare they would sell.

Luckily the package was insured so I received $100 refund for the damages from the seller. It was not packaged well at all...and I've learned to give good instructions for future boombox purchases. But for $150 this thing is PRETTY!

 

[Transistorized]

Glad we were able to help Now you can get a set of Tenergy 10,000mAh D's and rock that dude all day long

 

[BassHead]

Glad we were able to help Now you can get a set of Tenergy 10,000mAh D's and rock that dude all day long

Hell Ya! Blastin some Ultramagnetic MC's Critical Beatdown!!

Got Tenergy's on the way...but I got a heady stash of disposables and have been blasten out in the yard. Love this box. It really has some nice deep, punchy bass. It is my first Lasonic and have been pleasantly surprised.

Laconic's seem to always be listed as "parts boxes" on Ebay so I have always assumed that they may not be built to a high quality like some of the other brands, but this box is a little tank.