Petter Halonen

The problem is the one described above in this thread. It is the micrcontroller on mainboard. Sony did have the cpu with firmware, but it is now out of stock. I have equipment to change the cpu if I only can get one.

Does anybody know where to buy a new cpu for jbs980? Petter

I have concluded the CPU is toast, so I will try to find a used MD player to replase this one. And I think I will try to find one in ES series whit Atrac Type R or S, Actualy do not think they made ES whith Type S, so it will be Typer R then. Is it correct that the difference between Type R and S is that Type S is net-MD ? Petter Halonen

I got a new OP for the player, but stil no luck. Now the player is dead and only clicks twice when I put in the mainlead. I tried to force the power on, and I can se some strange digits in the display but nothing more. So I think there most be something the CPU detects that is wrong. I have no idea what this culd be. be.🤔🤯😩😩

It was defently not me resoildering them, I also noticed that, and mesured to see if there was any shorting. This pins (20 -25 ) are mostly 3.3V and clk signal or not in use and there were no shorings.

update: I managed to forse the power to say on, by shorting Q911. I used the FLIR cam to see if anythig got more warm than normal, but nothing got warmer than 42C which is normal for voltageregulators. Then I mesured all the voltages and everything is as it shuld be. So I guess this is the MCU that is messing things up because it detect or don't detect somthing.

I tried this, what happens is nothing or leds litt up like last picture randomly. Also tried different buttons to see what happend and it is the same. I have tried to disconect USB-board. Today I have got the Flir-cam so I will try to force the power on and see if anything get warm. I'll keep you updated.

I actually managed to get the standby led to lid now. I mesured on Q755 while I turned on the power, and the LED litt up. But now it is dead again... only when I put it in to servicemode it looks like picture below.

Thank you for the advice. I tried this as soon as I read your advice, but no luck. still goes directly to standby and refuses to take the disc if i try to put in the minidisc.

The problem now is that it switches to standby and I can't even get it in to servicemode. The backup battery is defect, only 0.4V by the way. There is no lite in the standby led. I only have 3.3V system and Back 3.3V. But I will not give up ... The fault is probably very simple thing when I find it. A friend of mine will bring over an Flir camera and we will try to disable the shutdown signal momentarily, just to see if something get to hot.

I mesured it between pin 3 on IC401 and GND, while the mainboard was disconected, so no frontboard, USB bord, BD board or powersupply board. Probably the MCU or leaking cap. does anybody have a player they culd mesure tis to see if it is ok or not?

My MD/player is still dead. I did disconect all the wires and put it aside for a cuple of weeks, but it did not help. Then I took out the mainboard only to discoverr that Sony took a shortcut and did not wash the card after running it trough soilderingbath. So I cleaned it in redspirit and put id to dry up. Now it is clean like it is suposed to be. I mesured the resistanse from different voltages to ground. one of them sticks out. The system 3.3V has only 66 ohm to ground. So I have to digg in to that and find out why. Here some before and after pictures of IC1 (Systemcontroll) There is some dust on across some pins on the afterpicture, I took them away.

Thank you for helping me. I'll start with disconecting everything and wait a cuple of days. I don't think I will put it in wather yet....

HI. I haven't had time to move forward, I tried to put the divice in service mode but it looked like on the picture below. I wil try to find time this week for repairing the player , as I love it very much, and was so proud to have it in my stereo. I have Tandberg amplifiers and cd-player, which maches well to the Sony MD-player.

During my search for the fault it changed from switching on, but no display, to switching on and and then off. So at the moment it switches of the rele and there is only system voltage (3,3V). What happend was that I mesured PDOWN on pin 4 CN3 and sudenly it switched off.