Re: Spice Ribbons Message #8 Posted by Vieira, Luiz C. (Brazil) on 2 Nov 2009, 12:49 a.m., in response to message #7 by Michael Meyer
Hi, Doc.;
could I say 'Good news, afterall!? Well, your HP34C is back to life, and this is always good news, right?
I have observed that the HP41 has the same problem, i.e., once the batteries contacts show corrosion, cleaning and/or replacing only the contact tips will not always stop corrosion to go inside the flex circuits. I have two unusable contacts+I/O assembly. If we consider the thickness of the copper tracks and the amount of chemicals that have already been in contact with them plus the atmosphere elements (mainly oxygen), it seems to me an additional neutralizing component is needed after cleaning the leakage so it does not go ahead 'eating' the cooper. I achieved some acceptable results with sodium bicarbonate solution (I hope this is the English term for that). It is normally used to wash recently corroded PCB to neutralize the ferric perchlorate (I also hope this is the correct term...) so the final PCB is not slowly corroded by the remaining perchlorate. BTY, did you use a computer flat cable to restore the HP34C? I have an HP38E waiting for a transplant that will happen today, if time is not against me, and I'll use it. Luckily I'll replace only the three-track part of the ribbon, not the whole flex circuit.
Hope you succeed bringing the HP32E back to life. It is a fine statistics-addressed Spice.
Cheers.
Luiz (Brazil)
Edited: 2 Nov 2009, 12:51 a.m.
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