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HP Forum Archive 10

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Spice battery flex circuit
Message #1 Posted by Renato on 20 Jan 2003, 9:58 p.m.

I got a flex circuit for a TV set - looks like I will be able to use this on my recently bought 34C. Has anyone tried something like this ?

      
Re: Spice battery flex circuit - built from scratch
Message #2 Posted by Renato on 22 Jan 2003, 8:56 a.m.,
in response to message #1 by Renato

Responding to myself. I abandoned the tv flex circuit and built a flex circuit from scratch - a "sandwich" with chomerics double sided copper laminated, and scotch tape as "bread". Not original, but much better that wire. Had some work soldering to the power supply board. The 34c is fine, survived surgery without consequences.

            
Re: Spice battery flex circuit - built from scratch
Message #3 Posted by Pyerre on 22 Jan 2003, 12:55 p.m.,
in response to message #2 by Renato

Hello Renato, There're various kind of flex cables can be stolen from old HDD's (used to connect the R/W heads to logic board). Those cables looked like the original one & could do the job. HTH, Pyerre

                  
Re: Spice battery flex circuit - built from scratch - Battery contacts
Message #4 Posted by Renato on 22 Jan 2003, 1:44 p.m.,
in response to message #3 by Pyerre

Thank you. Nice idea - let's see if I can find a hard disk for this organ donation. Also - what do you use for battery contacts ? I am going to try the metal that protects the window of 31/2" floppy disks , but suggestions would be welcome.

                        
Re: Spice battery flex circuit - built from scratch - Battery contacts
Message #5 Posted by David Smith on 22 Jan 2003, 6:28 p.m.,
in response to message #4 by Renato

Small Parts, Inc sells beryllium copper strip. It is IDEAL for making spingy contacts. For inferior results phosphor-bronze can be used. I use small aircraft rivets to attach the contacts. Small (#0) screws can also be used. Also SIG makes small brass eyelets that work well. You can get them at hobby shops that sell model aircraft parts.

As far as using flex circuits for replacing the original contact cable... way too much hassle soldering, etc. Just use small stranded wire. I get mine from the various motherboard connections to PC front panels.

                        
Re: Spice battery flex circuit - built from scratch - Battery contacts
Message #6 Posted by Pyerre on 22 Jan 2003, 6:33 p.m.,
in response to message #4 by Renato

Hi Renato, About the battery contacts, the "metal spring" type used as ESD purpose, the ones found inside the computer cabinets, could do the good job as well. HTH, Pyerre

                        
Re: Spice battery flex circuit - built from scratch - Battery contacts
Message #7 Posted by Renato on 23 Jan 2003, 8:44 p.m.,
in response to message #4 by Renato

David, Pyerre - thank you for your suggestions. I went to two hobby shops here in Brazil - they donīt carry rivets, eyelets or smal screws. I tried to find old computer cabinets, but had no luck yet. As for using wire in place of flex circuits. I have done that twice, but decided to try flex circuits, because I think that wire is too crude for these nice machines.

                              
Re: Spice battery flex circuit - built from scratch - Battery contacts
Message #8 Posted by Christof on 23 Jan 2003, 10:00 p.m.,
in response to message #7 by Renato

I've got two 32E machines undergoin restorative surgery right now. If anyone has picture to help me trace (some of the paths at the battery side are eaten to the point of non recongnizability......

I have considered tape and wire, but I think I may try using modeller's house elctrical wiring- which happens to be flat ribbon tape (with two copper conductors side by side)!

if you have a store that caters to hobbyists who work on model railroads and model houses (extravagant doll houses), you may find some.

for batteries, why not solder the leads from 2AAA cell srping holder? (assuming one will fit.) a pair or high cap aaa rechargables should work fine.

                              
Re: Spice battery flex circuit - built from scratch - Battery contacts
Message #9 Posted by Pyerre on 23 Jan 2003, 11:00 p.m.,
in response to message #7 by Renato

Hi, Take a look at your PC at home. Many of them are so equiped with those ESD metal spring clips installed between the cabinet's edges & the cabinet's cover. They're looked & work nice in my HP-33E. HTH, Pyerre

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