HP 30s screen & brain have been water-damaged, but I enjoyed this calculator

Tear them apart and clean the guts with a dry paint brush. It probably has some corrosion damage from the soaking.

Also, there are 8ea HP-30s calculators on eBay for an average prices of about $15/ea.

___________________ In hindsight, no buttons should have been pressed even after you wiped off the exterior of the calculator. That is - no circuits should have been allowed to complete - what happens when you press buttons on the calc. The calc should be dismantled - if readily so - and allowed to dry under a bright lamp or the sun. Reassemble and it *should* work like new. That was all that was spilt on it - water?

-CC

Done, nothing better.

Yeah, I know, but I even have a HP-50g, which is clearly better. That is not the problem. The problem is that I like(d) this calculator.

Yes, only water. The problem is that water was spilt on it not only all over one face, but over both faces.

After having opened it, etc., I also realized that the main board is slightly broken at its end: some circuitry portion is raised upward, showing some slight damage, probably done with a screwdriver. I assume that the whole stuff was sticking out because after having opened the calculator (to see this and to check connections) and closed it, it does not work anymore. I re-opened it, did my best to join both parts, but it does not want to work anymore. Is it ready for the trash? It only shows slight damage.

Thanks.

ht, no buttons should have been pressed even after you wiped

_______________ That slight damage to the circuitry may be all it takes. The width of the paths of those ciruits is designed to carry specific voltages with a specific resistence. If one is cut even slightly through the proper voltage(signal) will not reach its intended destination. That is all I know about that and someone else may have a better answer.

In addition, they may also have a better answer than the one already provided to the problem I posted about my JVC VHS-DVD combo video heads(!)

-CC

ight, no buttons should have been pressed even after you wiped

ave

to

Thanks. I'll wait for other messages. Such a pity. I liked this calculator :(

Thanks. I'll wait for other messages. Such a pity. I liked this calculator :(

Do you have a soldering iorn? If so you can fix the broken traces. It isn't that complicated with a little practice..

Maybe someone around here knows a good website for soldering techniques. Or just serarch the history of this group. It has been discussed many times.

Best of luck.

Mike

Did you actually take it apart? Here are HP's useless disassembly instructions (for recyclers):

Try washing it again with CLEAN water to remove any contaminants and salt crud. Use a paint brush for cleaning. Use an air compressor and air gun to blow off as much water as possible. Let air dry for at least 24 hours. Try again.

Yech. It's really an HP relabeled Kinpo calculator.

There's no exact equivalent but this is close:

This self test might be useful:

Yes, if taking apart means disassembling.

Thanks.

I'll try, but the broken board is surely not going to be influenced in some better way by this.

Thanks. If it ever works again, I'll try it. The problem is that, as written before, my calculator won't power on anymore, surely because of the broken board.

The screen problem was, considering

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Thanks. I'll try to get one, and to make it work. But chances to succeed seem to be very low: this is a thin board, just like there:

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Okay, you might check

for pictures of the problem. I could use a soldering iron, but would it ever come it to life?

(...)

Your Sony Ericsson K750 cell phone camera has a macro mode for close focus. Please use it. With the flash off, you might also need some more light.

If you have a broken trace, just scrape off the insulation with a small screwdriver and tin what's left of the trace with some solder. Then, take a fine wire (one strand from a piece of stranded hookup wire) and solder it over the tinned traces. This does take some practice.

Do NOT touch the epoxy mound with the calculator chip under it. Just pushing on the epoxy will break the wire bonds underneath.

I tried. Sorry, I had forgotten.

Here are some details:

I also noticed that there is some broken trace on another part of the board:

(`downmost' trace)

It seems that the broken part of the trace was too small to ever try introducing a wire there. After having pressed a lot, and tried to solder the whole (without an iron, okay), here is what I get:

I tried. Sorry, I had forgotten.

Here are some details:

I also noticed that there is some broken trace on another part of the board:

(`downmost' trace)

It seems that the broken part of the trace was too small to ever try introducing a wire there. After having pressed a lot, and tried to solder the whole (without an iron, okay), here is what I get:

It looks to me that the traces aren't broken... Only the green solder mask is scratched off. The solder mask is like a acrylic paint to keep stray solder from making a bridge between two different traces. Your problem is elsewhere.

And by the way do you know what macro mode on a camera is? It is for taking pictures of things that are very small and close. It ususally has a picture of a small flower on the button. You can focus on the board using macro mode without it being blurry.

Example

Anyhow.. I would check the batteries and see if they are properly seated and are in the correct polarity. Ex. + / - correct.

Take some more pictures and come back.

Good luck.. Mike

But the first one I shown is clearly broken, isn't it?

a bridge between two different traces. Yes. But, take e.g.

Okay, but where, then? I have checked polarities, and everything was working before opening it!

ng

I know.

Upsetting, as I _know_ what a macro mode is. For the first pictures of the thread, I had forgotten that it existed on my mobile phone. But, for the pictures I presented in my previous message, I used the macro mode. Sorry, but it is an old mobile phone (K750i), and the board reflects light. I *did* use the macro mode, and not the zoom. I'm not that stupid.

and

Checked.

Which pictures could I ever take? I have no other camera, and

I love old HP stuff. I still have my HP41C calculator and my HP2621a terminal. ANd they work fine. But I might suggest if your really love the HP RPN, to get a software version for your computer. There is one that has both HP12 financial and HP11 engineering modes by Osvaldo Ramos Tsan Hu, a chemical engineering professor. It works in Portable Apps off my USB fob.

- = - Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist

Yep. I have one on my iPod Touch:

Also one on my cell phone. None on my computah as I have the real thing handy. In the office, it's an HP35s. At home, it's an HP41cv. I've used algebraic calculators, but I much prefer RPN.

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