Technics SX-PR603 the display goes off need your help!

[cobra360]

Hi,C you help!

when i turn on the power for Technics SX-PR603 the display goes off with only the backlight on (blank blue flashing screen), and no sound is produce, and no sound from the headset either.

I should start with what do you think to check, I have the repair manual!, i don't want to move to many stock for startin'

Any help will be appreciate! Thanks in advance!

 

[happyrat1]

Power supply is working. Motherboard and / or display may require service.

Mucho expen$ive...

Unplug it...

Pick it up...

Shake it around...

see if anything is rattling inside?

That's where we start

Gary

 

[happyrat1]

Step 2...

IFF no rattle...

Open it up. Keep records...photos, notes, etc...

carefully remove ribbon connectors, spray with Deoxit and carefully reassemble, then test.

Step 3 is on a need to know basis IFF previous step failed.

cross yer fingers

Gary

 

[cobra360]

Power supply is working. Motherboard and / or display may require service.

Mucho expen$ive...

Unplug it...

Pick it up...

Shake it around...

see if anything is rattling inside?

That's where we start

Gary

Thanks Gary
Thats a start
Stay safe

 

[Jan46]

Hi Cobra360,

I had a similar problem with the SX PR703. After power on the only thing i get is a blue screen. First i thought the reset circuit was the problem but I figured out that this has to be a boot problem of the processor and the suspected item is the flash memory. I checked the connections to the chip IC11 and found one track that was broken, i repaired that but still no luck.
At the end i decided to re-solder all the pins of IC11 - i just melted the solder pin by pin - and YES the keyboard is functional again.

Hope that helps you. Be careful with static electricity, i have my soldering iron connected with 100k resistor to the ground-plane of the circuit board while soldering.

Good Luck
Jan

 

[mris]

Hi
As far as I can remember the power supply is divided into two sections.
section 1: + and - 15 voltage regulators
section 2: +VCC and -VCC for the power amplifier.
So check these voltages for the backlight and the sound.
Is there an error message on the screen ?
Good luck and stay safe
mris