This is an "out of curiosity" question. I have multiple backups of this unit,
and //do not// intend to repair it. I just want to see if anyone has any
interesting insights.

The unit is a D-FJ75TR, one of Sony's last "deluxe" Discmans. I'd been using
it to listen to CDs in bed, and yesterday it stopped working correctly.

When I install the batteries, or plug it into the adapter, it immediately
starts to play -- and none of the controls work. I can't pause it, change the
track, set the volume, etc. Nor do any of the controls on the remote/tuner
module work. (Unplugging the remote doesn't fix the problem. And the control
lock button isn't jammed.)

The "obvious" answer is CMOS lockup, which I've seen on other products.
Yanking the power while the device is running sometimes cures this, but not in
this case.

I'm not trying to start an extended, overwrought discussion. I'm just
wondering if anyone has any ideas.

Thanks.

On 30/11/2014 18:40, William Sommerwerck wrote:
This is an "out of curiosity" question. I have multiple backups of this
unit, and //do not// intend to repair it. I just want to see if anyone
has any interesting insights.

The unit is a D-FJ75TR, one of Sony's last "deluxe" Discmans. I'd been
using it to listen to CDs in bed, and yesterday it stopped working
correctly.

When I install the batteries, or plug it into the adapter, it
immediately starts to play -- and none of the controls work. I can't
pause it, change the track, set the volume, etc. Nor do any of the
controls on the remote/tuner module work. (Unplugging the remote doesn't
fix the problem. And the control lock button isn't jammed.)

The "obvious" answer is CMOS lockup, which I've seen on other products.
Yanking the power while the device is running sometimes cures this, but
not in this case.

I'm not trying to start an extended, overwrought discussion. I'm just
wondering if anyone has any ideas.

Thanks.

stuck contact of a key?

Stuck contact of a key?

The obvious one would be the Play button (as the unit starts playing when I
put the batteries in).

I'll try holding down the Play button on a "good" unit, and see what happens.

Some models had a "lock" switch to keep random hits from affecting the play while one is jogging or something.

HAHAHA, Sony thought people in this country jog !

"N_Cook" wrote in message ...

On 30/11/2014 18:40, William Sommerwerck wrote:
This is an "out of curiosity" question. I have multiple backups of this
unit, and //do not// intend to repair it. I just want to see if anyone
has any interesting insights.

The unit is a D-FJ75TR, one of Sony's last "deluxe" Discmans. I'd been
using it to listen to CDs in bed, and yesterday it stopped working
correctly.

When I install the batteries, or plug it into the adapter, it
immediately starts to play -- and none of the controls work. I can't
pause it, change the track, set the volume, etc. Nor do any of the
controls on the remote/tuner module work. (Unplugging the remote doesn't
fix the problem. And the control lock button isn't jammed.)

The "obvious" answer is CMOS lockup, which I've seen on other products.
Yanking the power while the device is running sometimes cures this, but
not in this case.

I'm not trying to start an extended, overwrought discussion. I'm just
wondering if anyone has any ideas.

Thanks.

stuck contact of a key?




I thought so too.


Gareth.

When the Play/Pause button is held down, a "good" unit misbehaves in exactly
the same way as the "bad" unit, whether or not the remote control is
installed.

The Play/Pause button isn't jammed, so it would seem the fault is somewhere in
the wiring.

I have the service manual. When I find it, I'll tear into the lid (which holds
the key pad). It couldn't hurt.

"William Sommerwerck" wrote in message
...
When the Play/Pause button is held down, a "good" unit misbehaves in
exactly the same way as the "bad" unit, whether or not the remote control
is installed.

The Play/Pause button isn't jammed, so it would seem the fault is
somewhere in the wiring.

I have the service manual. When I find it, I'll tear into the lid (which
holds the key pad). It couldn't hurt.


Assuming that it's one of the tactile 'dome' switches, it is very common for
these to 'collapse' and effectively fail short circuit. I know that you said
you were not looking to repair it, but it really is a very simple fix if you
can be bothered to take it apart.

Arfa

Assuming that it's one of the tactile 'dome' switches, it is very common for
these to 'collapse' and effectively fail short circuit. I know that you said
you were not looking to repair it, but it really is a very simple fix if you
can be bothered to take it apart.

Arfa

He said it wasn't collapsed, although there's the possibility some liquid was spilled in the key matrix and is causing an unintended function command.

But I've seen a few of these over the years where the scan lines can be unsoldered at the micro for a test and the fault remains. Sometimes it's a bad micro caused by a static discharge through the control board.

"John-Del" wrote in message
...


Assuming that it's one of the tactile 'dome' switches, it is very common
for
these to 'collapse' and effectively fail short circuit. I know that you
said
you were not looking to repair it, but it really is a very simple fix if
you
can be bothered to take it apart.

Arfa

He said it wasn't collapsed, although there's the possibility some liquid
was spilled in the key matrix and is causing an unintended function
command.

But I've seen a few of these over the years where the scan lines can be
unsoldered at the micro for a test and the fault remains. Sometimes it's
a bad micro caused by a static discharge through the control board.




I had a piano keyboard once that had lost some notes.
It turned out the scan IC scanned both the keys and the button/LED matrix
using part of the same bus. One LED was short circuited, which disabled one
line shared with the keys, taking out the whole bunch of notes.



Gareth.

"John-Del" wrote in message
...


Assuming that it's one of the tactile 'dome' switches, it is very common
for
these to 'collapse' and effectively fail short circuit. I know that you
said
you were not looking to repair it, but it really is a very simple fix if
you
can be bothered to take it apart.

Arfa

He said it wasn't collapsed, although there's the possibility some liquid
was spilled in the key matrix and is causing an unintended function
command.


Err, no he didn't. He said it wasn't jammed, which is an entirely different
thing. I replace many many of these buttons on a variety of equipment that
uses them, and it is not at all uncommon for the dome to collapse, whilst
the outer control button remains free to move.



But I've seen a few of these over the years where the scan lines can be
unsoldered at the micro for a test and the fault remains. Sometimes it's
a bad micro caused by a static discharge through the control board.


I've had one or two failed micros over the years, but compared to faulty
switches, the relative proportion is vanishingly small

Arfa

"Arfa Daily" wrote in message ...

Assuming that it's one of the tactile 'dome' switches, it is very common
for these to 'collapse' and effectively fail short circuit. I know that you
said you were not looking to repair it, but it really is a very simple fix
if you can be bothered to take it apart.

It's not a question of "bothered". I have to find the service manual so I can
"rationally" remove the lid. (It's not obvious how it comes off.) Once that's
done, it will be a simple matter to unscrew the panel covering the switch pad.

Thanks for your encouragement. Now, if I can get some help with the Lux
amplifier I damaged yesterday... (There's always John Curl.)