Sony MDP-850d laserdisc player NO DISPLAY - UK Vintage Radio Repair and Restoration Discussion Forum

Retrotechie · 15th Oct 2018, 10:17 pm

Hi all, does anyone have any experience of these ? I have never worked on a laserdisc machine before, although i own a couple (i have some pro models).
This one has no display, but is otherwise working fine.
I'm hoping its just one of this miniature fuses, but does anyone have any thoughts or even a manual before i whip the lid off ?

I'm also looking for a remote control.

Many thanks,
James

boxdoctor · 16th Oct 2018, 9:27 am

Is the display a back-lit L.C.D.? If so, it may be illuminated by an incandescent lamp, whose filament has gone O/C.
Just a thought, as I am not familiar with this model. Tony.

Retrotechie · 16th Oct 2018, 12:46 pm

Its a traditional fluorescent type display. I suspect its missing one of the voltage lines. I might pull it apart later and have a look.

Retrotechie · 16th Oct 2018, 8:40 pm

So, i have whipped the lid off, and located a board on the left hand side, that has two sections, one for RGB, and one for power. It has 5 IC protector fuses on it, and all check out ok.
Sadly, there are no markings on the PCB as to what the voltages should be.

The main switched mode PSU, is under the disc transport, and would require some disassembly by the looks of it.

To be continued...

boxdoctor · 17th Oct 2018, 6:17 pm

One of the problems occuring with the flourescent display on many machines using them (especially V.C.R.s, it seems) is dry joints at the heater connections from the display to the P.C.B.. This often is not immediately visible on inspection, and can best be checked by carefully re-soldering these connections. Tony.

Retrotechie · 21st Oct 2018, 9:21 pm

The unit has now decided not to power up at all. May just be bad start up capacitors but I need to try and source the manual before going any further with this unit.
Thanks for advice about the FL display, will keep this in mind.

boxdoctor · 25th Oct 2018, 3:20 pm

You seem to be having trouble sourceing the service manual. Try this: http://freeservicemanuals.info/en/se.../Sony/MDP850D/ Click on the model nr. in the "type" box
Looks like your model. Tony

Retrotechie · 25th Oct 2018, 10:23 pm

Thats a really useful site, not come across that one before.
Ive downloaded the manual and will take a closer look in due course.

Thanks again !

ntscuser · 31st Oct 2018, 4:48 pm

Fabulous player! We had one for laserdisc demos. It was fun watching the front panel drop down before the tray ejected, I was half expecting the theme from Thunderbird 2's launch sequence to play. The RGB output was a also boon for monitors without an NTSC color decoder in them.

15th Oct 2018, 10:17 pm	#1
Retrotechie Pentode Join Date: Apr 2011 Location: Bromley, Kent, UK. Posts: 234	Sony MDP-850d laserdisc player NO DISPLAY Hi all, does anyone have any experience of these ? I have never worked on a laserdisc machine before, although i own a couple (i have some pro models). This one has no display, but is otherwise working fine. I'm hoping its just one of this miniature fuses, but does anyone have any thoughts or even a manual before i whip the lid off ? I'm also looking for a remote control. Many thanks, James

16th Oct 2018, 9:27 am	#2
boxdoctor Rest in Peace Join Date: Sep 2010 Location: Ripley, Derbyshire, UK. Posts: 785	Re: Sony MDP-850d laserdisc player NO DISPLAY Is the display a back-lit L.C.D.? If so, it may be illuminated by an incandescent lamp, whose filament has gone O/C. Just a thought, as I am not familiar with this model. Tony.

16th Oct 2018, 12:46 pm	#3
Retrotechie Pentode Join Date: Apr 2011 Location: Bromley, Kent, UK. Posts: 234	Re: Sony MDP-850d laserdisc player NO DISPLAY Its a traditional fluorescent type display. I suspect its missing one of the voltage lines. I might pull it apart later and have a look.

16th Oct 2018, 8:40 pm	#4
Retrotechie Pentode Join Date: Apr 2011 Location: Bromley, Kent, UK. Posts: 234	Re: Sony MDP-850d laserdisc player NO DISPLAY So, i have whipped the lid off, and located a board on the left hand side, that has two sections, one for RGB, and one for power. It has 5 IC protector fuses on it, and all check out ok. Sadly, there are no markings on the PCB as to what the voltages should be. The main switched mode PSU, is under the disc transport, and would require some disassembly by the looks of it. To be continued...

17th Oct 2018, 6:17 pm	#5
boxdoctor Rest in Peace Join Date: Sep 2010 Location: Ripley, Derbyshire, UK. Posts: 785	Re: Sony MDP-850d laserdisc player NO DISPLAY One of the problems occuring with the flourescent display on many machines using them (especially V.C.R.s, it seems) is dry joints at the heater connections from the display to the P.C.B.. This often is not immediately visible on inspection, and can best be checked by carefully re-soldering these connections. Tony.

21st Oct 2018, 9:21 pm	#6
Retrotechie Pentode Join Date: Apr 2011 Location: Bromley, Kent, UK. Posts: 234	Re: Sony MDP-850d laserdisc player NO DISPLAY The unit has now decided not to power up at all. May just be bad start up capacitors but I need to try and source the manual before going any further with this unit. Thanks for advice about the FL display, will keep this in mind.

25th Oct 2018, 3:20 pm	#7
boxdoctor Rest in Peace Join Date: Sep 2010 Location: Ripley, Derbyshire, UK. Posts: 785	Re: Sony MDP-850d laserdisc player NO DISPLAY You seem to be having trouble sourceing the service manual. Try this: http://freeservicemanuals.info/en/se.../Sony/MDP850D/ Click on the model nr. in the "type" box Looks like your model. Tony

25th Oct 2018, 10:23 pm	#8
Retrotechie Pentode Join Date: Apr 2011 Location: Bromley, Kent, UK. Posts: 234	Re: Sony MDP-850d laserdisc player NO DISPLAY Thats a really useful site, not come across that one before. Ive downloaded the manual and will take a closer look in due course. Thanks again !

31st Oct 2018, 4:48 pm	#9
ntscuser Hexode Join Date: Mar 2013 Location: Coventry, West Midlands, UK. Posts: 280	Re: Sony MDP-850d laserdisc player NO DISPLAY Fabulous player! We had one for laserdisc demos. It was fun watching the front panel drop down before the tray ejected, I was half expecting the theme from Thunderbird 2's launch sequence to play. The RGB output was a also boon for monitors without an NTSC color decoder in them. __________________ Classic TV Show Theme Tunes