The new laser assembly has now arrived, and it looks exactly as it should do – complete with Chinese labels. It is obviously a pattern part rather than a genuine Sanyo one but appears identical to the one I need to replace.
There are a couple of issue to be aware of if you are attempting a similar repair. There are two variants of the SFP101N – one of them has 15 pins on the laser head, and the other has 16. I don’t know what the practical difference is, but you do need to make sure that you order the right one. The only way to do it is to count the pins which are on a flexible ribbon cable which plugs in to the main board.
The other thing which is important, and which is not entirely clear in the packaging of the new unit is that there is a solder bridge on the laser head which needs to be removed. This is apparently something to do with antistatic precautions, although it is a strange thing. The only way to remove it properly is with a solder sucker. I’ve always had some trouble with desoldering, and in the past I’ve used a soldering iron and a spring loaded pump. This is always a bit fiddly and I’ve had variable success. However, I came across this in the CPC catalogue lately:
This is a simple combination of a solder pump with a heating element on the tip – so you can heat up the joint and as soon as the solder has melted suck it up in one go.
Here is the new part with the solder bridge intact (circled in red):
And here it is again with the solder bridge removed. It was simply a case of letting the iron warm up, pressing the tip down on the solder for a few seconds and pressing the button to release the plunger. The result was better than I had hoped – the bridge is completely removed leaving the two pads clean.
You can see the white connector block just to the right of the bridge – this is where the 16 pin ribbon cable plugs in.
Having got the new module prepared, I now need to install it. Getting the old one out was actually quite easy – the service manual gives details of all the screws etc and I was able to remove the large plastic tray assembly which contains the laser. The awkward bit was disconnecting a few of the connector blocks and the flat ribbon cable although generally with a bit of gentle pressure these came out.
The second picture shows the laser mounted in a plastic housing which fits in to the bottom of the tray itself.
Replacing it was a pretty simple matter, just a question of removing the two screws that can be seen above and then pulling the mount out of the the housing by flicking past a few clips. Then there were some rubber boots to come off and then everything put back into place. It was actually pretty easy and I then put the whole thing back together again.
I then took a deep breath, turned the power on and put a disc in…
Success! The disc reads and plays perfectly, and after a long period of testing I’m pretty confident that the problem is now solved. Needless to say I’m pretty chuffed – I’ve repaired the player at minimal cost and in a much shorter time than I expected. If I had had to buy new I would have had to spend at least £180 and I’m very pleased to have avoided this. Also of course… I have enjoyed the adventure of fixing it.