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Usage ?
I have a machine and have fitted new batteries.


Vintage user 70+ !!


Welcome aboard!


P.S. To clear that message just press the "<-" key.

Edited: 18 Oct 2013, 3:51 p.m.

Many Thanks. I have manuals but cannot find the procedure for removing NONEXISTENT and using the HP. Please advise

When first powered on the 41C should give you a "MEMORY LOST" welcome. From there you can press

and see

If the first thing you saw after pressing ON was a

message then something's wrong.

You could try to power it off, press

keep it pressed and push the ON key, then release ON, then <- . You should see "MEMORY LOST".

Be warned that this will wipe all memory, if you have programs or data inside, they won't survive.
Please try and advise.

Also check appendix B Maintenance and Service


Edited: 19 Oct 2013, 6:31 a.m.

If there is a ROM in it; take it out while the calc is switched off and try it again. If not:

It could still have a program that is trying to auto execute when you turn it on, and it's calling to a ROM or peripheral. It would normally beep though. No matter. Just do a "memory lost" like Massimo says and if that's the problem; it will go away. You gotta start somewhere.

Attempted- Memory Lost does NOT appear.

Comments ??

How do I remove ROM.

70+ user

Just to make sure you did not miss something, here's the detailled procedure to clear your 41CV completely:

1. Turn the calculator off. You will see a blank display.

2. Press and hold down the [<=] (left arrow) key. It is the rightmost key in the same row as the big ENTER key.

3. While you still keep the [<=] key held down, simultaneously press and then release the [ON] key with your other hand.

4. Release the [<=] key as well. You should now see MEMORY LOST.

5. Press [<=] to clear this message and see 0.0000

Does this work?


Regret Does NOT work. Trying to revive an old M/C

Hi Bry

just had to say that!

The CV is a great machine and programming it with elegant routines is better then doing crosswords or sudoka.

Location of the ROM modules:

Turn off Calc and remove the modules at the north (top) end of the case (see above).

Follow Dieters suggestion above, if memory lost occurs, good. The calc is reset. If "nonexistant" occurs it sounds like a memory or internal PCA ROM problem.

All is not lost. Remove the batteries and let the calc sit for a few days. Some people accelerate this process by shorting the internal battery contacts in the machine. The far left shorted to the far right. There are a few more procedures but these are the safest. I am saying this as your posting indicates a level of knowledge about the system that is not as technical as some here have.

contact me by email geoffqf@telusNOTnet and substitute . for not.

So follow the procedures above and see what happens, if nothing email me or post again.

cheers, Geoff

ps i have to state, make sure the batteries are N size 1.5 volt alkaline.

there are 6.0 volt alkalines out there that fit and are used in home security systems. Of course, nonexistant would not show up on the screen, instead smoke!

Edited: 20 Oct 2013, 4:58 p.m.

I am saying this as your posting indicates a level of knowledge about the system that is not as technical as some here have.
Certainly !!Knowledge is PoorCertainly !![/bold

contact me by email geoffqf@telusNOTnet and substitute . for not.

[bold]Please explain Message not accepted

Email sent via this posting board so you should have a message now.

Also my email is geoffqf@telus(dot)net. Replace the word and brackets: (dot) with a "." period without the quotes.

Example: gezzzz@telus.net