Preferred Battery Compartment Cleaning Method?

[AVITWeb]

Hello folks. Here we go again.

I just purchase an NH900 from EBay, and with the exception of what looks like a power problem, it is in good shape.

That being said, I had noticed that a fully charged battery was showing up as almost dead and the unit itself was not staying on very long when when charging. Long story short, it looks like some corrosion at the back end of the battery compartment and some that has seeped under the plastic covering the metal plate at the battery door.

Have any of you folks had success with certain types of contact cleaning methods? Maybe a good way to clean up as much of the corrosion as possible?

I had found another thread where someone linked another thread to it, but the link was dead.

Thanks in advance...I really want this thing to work out and if I can get rid of this "little problem" all will be well.

[PhilippeC]

I am also interested by any answer about that "little" problem

[sfbp]

You need a jeweler's screwdriver.

[AVITWeb]

Any idea as to a liquid that might help? I had hear alcohol but wanted to see of anyone had had success with it

[sfbp]

Isopropanol 99% or better. But my point was, you're not really going to get all the guck out of there unless you're prepared to take the unit apart.

[AVITWeb]

Oh, I know what you were getting at. Disappointing really to be one of those things that should be on the top of my list to check but did not. Thanks for the input.

[punkrockaddict]

I recommend contact cleaner spray.You can use an old toothbrush and a small screwdriver to scratch off the corroded parts.

;-)

[AVITWeb]

Thanks punkrockaddict. Auto supply store?

[sfbp]

Be very very careful spraying contact cleaner into your md units. You will literally never lose the smell. Spray some onto a rag and use the rag (or a qtip).

The combination of isopropanol and a very sharp knife has done wonders for me.

[AVITWeb]

That's the first thing I thought. Thinking more a cotton swab sprayed with the cleaner or alcohol.

[Sargaso]

I usually manually clean away the bulk of the residue then use a q-tip moistened with wet baking soda. Baking soda will bring back a neutral ph. Make sure everything is dry before applying power afterward.

Looking at the service manual for the NH900, the negative contact for the battery (back end of the battery compartment you mentioned) appears to be on the main PC board itself. If there is leakage on the main board you may have to disassemble the unit to clean and repair any damage. Good luck.

[AVITWeb]

Sargasso. Luckily it looks to be just a small blot of green on the bottom. And that is in the contact itself. It does not appear to have "seeped" anywhere like the battery door.

Thanks all for the advice!

[punkrockaddict]

The spray iam talking about is "Tuner 600"

Very well product..Leaves no residents on the contacts and all my Units don't smell :-D

Therefor I actually like its smell when spraying ;-D

Just google for it and you'll see what this one actually does.

[sfbp]

Sargasso. Luckily it looks to be just a small blot of green on the bottom. And that is in the contact itself. It does not appear to have "seeped" anywhere like the battery door.

Thanks all for the advice!

On the **bottom**???

OK, if so, the knife is your best weapon, followed by cleaning of what the green guck was touching. If you meant the TOP, then it's time (anyway, since you have to take it off to get at the bottom too) to learn how the battery door comes off and how to play with the spring so that it pushes firmly onto whatever battery you have in there.

It's highly likely you will want to do a "power adjust" (as opposed to Laser Power Adjust). The other thing is to get a new battery, or attempt to recondition the old one using the BC700 (or similar) computerised charger.

Whatever you do, do NOT do a complete (911 reset) service, because you won't have the tools.

[AVITWeb]

Looks to be a small blot of green on the contact. I will probably not mess with any adjustments of my own at this point. I will clean it the best I can and see how it goes. If I still have an issue, both of my 900s will be going to Jim and the new one will be sacrificed for any parts needed for my original unit. I was able to get the plastic battery door off of the hinge assembly.

[sfbp]

which contact? + or - ???

[AVITWeb]

Sorry. Bottom (back of battery compartment at the negative end.) most of the mess is at the top on the battery door hinge.

[sfbp]

You'll need to get it open and clean up the springy contacts that touch the -ve pole of the battery.

Even with it all clean, the likelihood is that the charging circuits and the general power of the unit needs a twiddle.

[AVITWeb]

I am soooo afraid to open these things because they mean a lot to me. I am really scared that I will end up busting it. Especially after looking at the service manual and for disassembly there is a note that says "remove solder. "

[sfbp]

No solder removal; you can get the case apart to clean up the battery quite easily, provided you have the right screwdriver and are willing to be very careful to fit everything together without tightening too much as you re-assemble. "Meccano skills", 'tis all, since if you know Rev. W. Awdrey you undoubtedly know Meccano.

[AVITWeb]

Really? I have the tools. I just don't see how to do it in the SM. Can I just unscrew the bottom screws and release the back of the player to expose the battery compartment?

[sfbp]

That's how it works. Look at the diagram, you can remove the bottom case only one way

[AVITWeb]

Thanks! I will give it a try!