The Museum of HP Calculators

HP Forum Archive 19

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HP41C x-ray
Message #1 Posted by Thomas Klemm on 29 Mar 2009, 1:19 p.m.

Found an x-ray print of an HP41C here.

      
Re: HP41C x-ray
Message #2 Posted by Randy on 29 Mar 2009, 8:01 p.m.,
in response to message #1 by Thomas Klemm

FWIW, it's a very late model C fullnut with card reader and modules installed. Pretty neat! Thank you.

            
Re: HP41C x-ray
Message #3 Posted by Dan Grelinger on 30 Mar 2009, 10:09 a.m.,
in response to message #2 by Randy

What module(s) are installed?

                  
Re: HP41C x-ray
Message #4 Posted by bill platt on 30 Mar 2009, 4:14 p.m.,
in response to message #3 by Dan Grelinger

Randy is a superman of calculators but he'd need X-ray interpretation clairvoyance in addition to X-ray vision to tell that ;-)

                        
Re: HP41C x-ray
Message #5 Posted by Dan Grelinger on 31 Mar 2009, 11:37 a.m.,
in response to message #4 by bill platt

Bill,

Maybe. But I think I see clues that would allow someone to identify at least one of the ROMs. ;-)

Dan

      
Re: HP41C x-ray
Message #6 Posted by Ed Look on 31 Mar 2009, 12:03 a.m.,
in response to message #1 by Thomas Klemm

Um... the x-rays won't harm the chips?

            
Re: HP41C x-ray
Message #7 Posted by Michael de Estrada on 31 Mar 2009, 12:37 a.m.,
in response to message #6 by Ed Look

Do the X-ray machines at airports damage electronic equipment?

                  
Re: HP41C x-ray
Message #8 Posted by Garth Wilson on 31 Mar 2009, 12:47 a.m.,
in response to message #7 by Michael de Estrada

My cameras and calculators have gone through airport X-ray machines many times with no damage or memory loss.

            
Re: HP41C x-ray
Message #9 Posted by Mike Morrow on 31 Mar 2009, 12:48 a.m.,
in response to message #6 by Ed Look

I've been passing my HP42S, HP50g, and HP17BII almost daily through the x-ray screening at a U.S. nuclear power plant for many years. It's at least as penetrating as the airport version. Before that, my HP-41CX and HP-15C made daily trips through the machine.

I'd say empirical evidence says that there's little to fear.

                  
Re: HP41C x-ray
Message #10 Posted by Michael de Estrada on 31 Mar 2009, 1:16 a.m.,
in response to message #9 by Mike Morrow

Actually, it's all about the dose rate and the vintage of the IC's. Dose rates less than about 5000 rad gamma will not hurt anything, and I think X-ray machines are way below that level. Also, older IC's are more robust than newer ones because they keep reducing the size of the circuitry. I had one project where I had to source some new old stock IC's manufactured before 1985 to ensure that they were made on a larger circuit gage to withstand radiation within reactor containment.

Edited: 31 Mar 2009, 11:52 a.m. after one or more responses were posted

                        
Re: HP41C x-ray
Message #11 Posted by Ed Look on 31 Mar 2009, 11:36 a.m.,
in response to message #10 by Michael de Estrada

I see. I was wondering because of talk in the past about radiation-hard components. This made me think that the old silicon could not handle higher energy radiation.

                        
Re: HP41C x-ray
Message #12 Posted by Mike Morrow on 31 Mar 2009, 7:11 p.m.,
in response to message #10 by Michael de Estrada

Quote:
Actually, it's all about the dose rate and the vintage of the C's.

The total integrated dose is typically more significant than the dose rate.

Quote:
Dose rates less than about 5000 rad gamma will not hurt anything, and I think X-ray machines are way below that level.

You've cited a dose, NOT a dose rate. Dose rate is expressed in RAD per unit of time.

The dose received in a typical x-ray screener is likely at least six orders of magnitude smaller than the value cited.

                              
Re: HP41C x-ray
Message #13 Posted by Michael de Estrada on 31 Mar 2009, 7:39 p.m.,
in response to message #12 by Mike Morrow

Yes, you are absolutely correct. I should have said that the threshold TID for damage to ICs is above 5000 RAD gamma. During a lifetime of passes through an X-ray machine, the TID would be much lower.

      
X-RAY from five TI calculators
Message #14 Posted by Joerg Woerner on 31 Mar 2009, 11:51 p.m.,
in response to message #1 by Thomas Klemm

You might watch these images, too:

X-RAY

Enjoy!

Regards, Joerg


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