HP 32E Display Question

[Harry (Germany)]

I have a HP32E, wich has a display problem. When I switch it on, all the upper left segments are missing. This problem disappears after a few seconds. But pressing a key sometimes produces the same thing, but only in the first 2 minutes of operation.
Does anybody know what that is?

There is also another problem, one of the dots is missing, I changed it to comma as radixmark, so its not a big deal now.
I think it has to be the led itself that is bad, could it be anything else?

Regards, Harry

[Nelson M. Sicuro (Brazil)]

I have a HP32E too, and when it arrives (I bought it through eBay) its display was horrible, digits missing, half-digits. I begin the restoration, and I found that my 32E is that version that the chips isn't soldered (as its display). I disassembled it and begin restoration, cleaning the contacts with a soft pencil eraser. When I assembled it again it was working as new!

Look at http://www.hpmuseum.org/tech30.htm

As your 32E is showing the same simptoms as mine I guess that it is the solderless version too.

In less words: bad contacts, a good cleaning will fix it.
But take care, the case is tricky to open, and the chips just jump away when you take the holders off!

Good luck.

Nelson

[David Smith]

Before working on any HP calculator record the positions of any wires (HP65/67 card readers) or chips (unsoldered spice series machines). A few closeups with a digital camera can come in really handy.

[Harry (Germany)]

I also resoldered all the contacts.
I don't think it is a bad contact, as the problem only appears in the first minutes of operation.

Regards, Harry

[Vieira, Luiz C. (Brazil)]

Hi, Harry;

have you also soldered all terminals in the mani chip? As the display connections end there, maybe you have a bad contact in the main chip itself instead of the LED assembly.

Anyway, if you look carefully, you'll see that the soldering tabs in the LED assembly are pressed to it, not soldered. I once applied solder material to each connecting point in the LED assy and the display worked fine again. I consider this a "last alternative", because when a complete set of segments is missing, I consider a bad connection. Have you also gently "twisted" the case when it happens? If it is indeed a bad connection it will probably restore their normal operation at the moment you do it.

If you still need help, let us know.

Luiz (Brazil)