Vivitar 285HV service advice: How to disassemble?

Hello:
I am new to this forum, so greetings to you all.
May a call for some help. I have an exploded batteries 285HV and want to open it for a good cleaning, since the rust is very heavy.
I do know the risks, but the unit has quite a time without batteries and I safetely discharged it with 100Kohm between terminals.

I tried taking off the visible screws, but the chasis has some trick to open it and I don´t want to force it.
Can somebody help in this? any exploded view is available? or instruction?

I googled for this info. but no useful info was obtained

Thaks you in advance.

Fernando
Montevideo, Uruguay

Greetings Fernando, and welcome to the APUG forums. Do you have a service manual, or similar, for this unit? I cant tell you how to do this myself, but I suspect there are plastic tabs that snap into place when they assembled this unit. If you can locate these tabs (or similar attachments) you may be able to pry them out GENTLY with a small flat blade screwdriver. This is a common way to assemble plastic parts so they dont need to be screwed together, and to keep people from taking them apart - so they dont get shocked with the high voltages, etc. You may want to try a Yahoo or MSN search, see if you can find the diagrams or service manual. Or hopefully someone else can point you to these items online.

I hope this helps you.

Paul

pauliej
Most flash units have screws hidden beneath decorator plates to prevent tampering. Although you have discharged the unit I always check voltage across the main cap once I have access to the leads just to be safe.

I haven't taken a 285 apart for years. 283s are pretty similar though. If the 285 has an aluminum plate on the side opposite the calculator dial it can be peeled off & may have a hidden screw beneath it.

Use alcohol to soften the adhesive & let it work for a couple of minutes. Gently pry the edge up with something like an Exacto knife & try not to crease it. If the blade goes in close to parallel you should have no problem.

Thanks you

Dear friends,

thanks you for the tips.
The indications are very correct.
My 285 is Chineese made from the 90´s.
It does has an aluminum plate opposite to the calculator, and beneath it it has a clamp. The adhesive was very soft, no need for alcohol

So the thing went this way:
2 screws on the hot foot
2 screws around the calculator
1 screw around the alu.plate
1 metal clamp under the alu. plate

After that you have to force a little the plastic case for hidden clamps

The printed circuit board is a bit untidy and components are not poorly soldered. I think this is due to the early chineese manufacture. I would expect better jobs in the newer 285s

Thaks to all
Fernando