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Adding a crystal to the wp34s - how?
Message #1 Posted by Cristian Arezzini on 10 July 2011, 6:22 a.m.

I just received the components to add a crystal to the repurposed 30b (thanks Eric). I opened the calculator, and it's quite obvious where I should put the crystal; but I have no idea where to put the capacitors (there are many empty pads), and I couldn't find any info around. So... Where do the capacitors go? :)

Thanks, Cristian

      
Re: Adding a crystal to the wp34s - how?
Message #2 Posted by Paul Dale on 10 July 2011, 6:29 a.m.,
in response to message #1 by Cristian Arezzini

They go immediately to either side of the crystal.

They are labelled C3 and C4 on the 20b's PCB.

- Pauli

            
Re: Adding a crystal to the wp34s - how?
Message #3 Posted by Walter B on 10 July 2011, 6:50 a.m.,
in response to message #2 by Paul Dale

... and they are really small. Precision soldering :-/

Walter

            
Re: Adding a crystal to the wp34s - how?
Message #4 Posted by Cristian Arezzini on 10 July 2011, 6:59 a.m.,
in response to message #2 by Paul Dale

OK, thanks! They really are smaller than I expected... I hope I won't damage anything!

Cristian

                  
Re: Adding a crystal to the wp34s - how?
Message #5 Posted by Etienne Victoria on 10 July 2011, 8:51 a.m.,
in response to message #4 by Cristian Arezzini

For my 47 years old eyes, a magnifier was mandatory.

Also, no ristretto or Red Bull for 12 hours prior to the modification and you should be set.

Steroids necessary to open the 30B case.

I succeeded by pressing hard on the side with thumb and inserting a FINE PLASTIC spudge in the opening whilst keeping the central part flat with the palm.

And yes, you need 3 hands for this: my daughter helped on this one :-)

Etienne

Edited: Didn't notice that Cristian had already opened the case. Sorry

Edited: 10 July 2011, 11:35 a.m. after one or more responses were posted

                        
Re: Adding a crystal to the wp34s - how?
Message #6 Posted by Marcus von Cube, Germany on 10 July 2011, 11:07 a.m.,
in response to message #5 by Etienne Victoria

HP should have added the capacitors, at least. I don't think it adds to manufacturing costs in any sensible way.


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