Saturday, October 23, 2010

Sony DSC-F828 loose lens turret - part 2

Hi and welcome back again folks.

In this part of my post, I'll describe to you more or less what tools and so forth is needed and give some start up tips.

OK - first up lets get some tools and a work area sorted out. You will need:

  • A good size, clean and uncluttered work space.
  • Good strong light.
  • A free standing magnifying lens, preferably the illuminated type.
  • Size 000 Phillips Head jeweller's screw driver.
  • White towel work mat.
  • Small, flat blade pliers.
  • A copy of the DSC-F828 service manual.
  • Small white bowl for screws, and small box for larger parts
  • Petroleum jelly
  • 'Locktite' or similar
  • Anti-static earthing system
The pliers I selected are used primarily for handling the flexible printed circuit ribbon cables or 'boards'. The ribbons need to be gripped carefully and gently and pushed or pulled evenly, slowly and accurately into or out of their terminating slots. (See the diagram below provided by Sony in their Service Manual). The flat pliers shown, not having teeth or serrations, will provide the best grip without the risk of damage.

6" flat blade pliers are recommended.
The jeweller's screw driver should be the type that you can push down hard against a rotating head piece in the handle to stop the bit riding up out of the screw head slot while turning. In order to get extra purchase on the screw while applying a load, it should have a reasonably big handle for you to grip. It should also have an extension piece to allow you to reach into hard to get corners.

This type of jeweller's screw driver provides the best reach and gripping power

The service manual for the 828 is not absolutely essential for this job as hopefully I have provided all the information necessary and plenty of photos. Still, I think it is a very useful guide and seeing as it can be found on the internet fairly easily and free of charge, it is probably worth the extra effort. Try

I strongly recommend you consider using an anti-static mat, and wrist strap to bond yourself and the work bench to earth while working on the 828. This is easily overlooked as being an unnecessary inconvenience but the problem with static is well documented and static discharge counter-measures are standard practice in professional workshops. It is not hard to do, can be used many times, and pays for itself in avoiding unnecessary damage.

Keep the work area clean and tidy. Drinks, food stuffs or other contaminants on the work bench invite disaster. Work as much as you can in a dust free environment. Place all parts together in a small box that can be labelled and sealed. Any static sensitive components should be stored in anti-static bags.

Here are some tips from the Sony Service Manual.

  • Check the area of your repair for unsoldered or poorly-soldered connections. Check the entire board surface for solder splashes and bridges.
  • Check the interboard wiring to ensure that no wires are "pinched" or contact high-wattage resistors.
  • Look for unauthorized replacement parts, particularly transistors, that were installed during a previous repair. 
  • Look for parts which, through functioning, show obvious signs of deterioration. 
  • Check the B+ voltage to see it is at the values specified.

Flexible Circuit Board Repairing:
  • Keep the temperature of the soldering iron around 270°C during repairing.
  • Do not touch the soldering iron on the same conductor of the circuit board (within 3 times).
  • Be careful not to apply force on the conductor when soldering or unsoldering.

Beware of the dreaded Capacitive Discharge Flash-unit. The follow again is with thanks to Sony:

As for human factors - here are a few tips for success from my experience working in Aviation Quality and Safety management. I don't think they will go astray here:

  • Read and study the method for repair so you have a good understanding of what is to be done and how to do it.
  • If you are not sure about something, then ask.
  • Work in short sessions then take a break.
  • Review every step you have taken. Look at it from all angles and think carefully about the consequences of what you are doing. For example when screwing something down, have you pinched something else? When unscrewing something, is there a loose piece that can fall off and be lost or broken, e.g. a ferrite bead.
  • If you feel you are having to push or pull hard, exert force or are having to lever anything then you are doing it wrong - stop, look and study what the barrier is because you will probably break something if you keep going.
  • If you feel frustrated, inclined to swear or curse then stop. It should be a pleasant experience and if it's not then you are probably doing it wrong. Stop, take a break, review the situation and then start again on a different tack.
  • If you feel tired, unwell, rushed, or if you have taken any drugs, alcohol or medication that can affect the quality of your work, then stop. Any kind of visual impairment, steadiness of hand, or rationale of thought is a barrier to success.
OK, in part 3 we move on to disassembly.

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