41CV Problems



#7

With fresh batteries, when I turn it on, there is no visible response. When I push "<-" while turning it on, at the release of the <- key, I get 6 commas, 1234 flags, PRGM, and ALPHA indicators on the right side of the display. This lasts for about 1 sec before turning off. It doesn't fade as in the post below, but goes off instantly. If I hold down a number key while turning it on, the same display stays on until I release the number key. If I hold a function key while turning it on, the function is displayed for a second, and then the commas (etc...) display until I release the key.

Clues, anyone? Thanks, in advance.


#8

Seems like a contact problem.

Are the case halves somehow 'squeezeable',

or in other words, do the screws seem to not

hold the halves tightly together?

If this is the case, you could *CAREFULLY* try to fasten the screws.

I wrote 'carefully' because if you screw too hard,

the plastic posts inside are likely to break.

Another idea: Is there any corrosion inside the battery compartment?

If yes, it's still a contact problem.

There's also a chance that the zebra stripes,

which do the contact between the CPU board

and the keyboard pcb, is faulty.

There are several other possibilities for malfunction,

but first try the first option.

HTH

Raymond


#9

You know, I had intended to address those items in my first posting, but forgot to. The case seens tight. I know sometimes it can seem tight, but still be loose, so I squeezed it anyway, and it made no difference. There is no battery corrosion.


#10

Okay...

Eventhough the case seems tight, I took it apart, and yes, the bottom posts are cracked. Without the screws in place, I pressed all the contacts together, and it worked! Put it back together, and it doesn't work, even squeezing it together, but at least we know what the problem is. I trust fixing the posts will do the trick. Thanks for prodding me on, Raymond.


#11

It is hard to repair the psts. It is much better if you get longer screws. Those coming from halfnut models are perfect.


#12

Also screws coming from the HP67 and other similar calculatoes are quite good replacements.

When I repair HP-67s I usually leave out the screws that go under the label, so I have a small surplus of these screws and use them for my HP-41 repairs.

**vp


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