Help please - HP-32 and 82143A printer

[Jim Creybohm]

1) My friend has asked me to see if I can get his 32S working again. Keys 4,5, and 6 don't work. I keep reading about heat stakes, and this has me a little concerned. Has anyone done this and if so, what should I watch out for? Oh, and just how easy/difficult is this? I am working on him to sell me this "antique". Unfortunately, like any good engineer, he is well aware of how good an older HP is and he is reluctant to part with it.

2) Has anyone posted information on rebuilding the C cell packs in the 82413 printer/plotter series? Is it here in the Museum, because I can't seem to find it is there is one. If not, then I'll have to take some pictures when I do mine up. If there is, would someone kindly post a link to it?

Thank you.

12345

[Vieira, Luiz C. (Brazil)]

Hi, Jim;

I posted some info last year (first sememter) about reusing Motorolla cellular cells to rebuild the HP82143A (and some HPIL devices, plus Topcats HP9x series as well) battery pack. I have the images but I'll dig the hard disk up so I can find the text. I'll post later about this, O.K.?

cheers.

Luiz (Brazil)

Edited: 27 Feb 2004, 10:48 p.m. after one or more responses were posted

[Jim Creybohm]

12345

[Vieira, Luiz C. (Brazil)]

Hello, Jim;

As I mentioned, here goes the picture I have. This image is based on actual scanned images from actual components and they are all in the same scale (proportional).

Unfortunately I did not find the original text I wrote at the time I mentioned these first. But there's no much mystery:

1 - empty battery holder (HP82143, Topcats, HPIL tape driver, etc.)

2 - original battery assembly (outside the battery holder)

3 - complete battery pack rebuilt with rechargeable NiMH cells from Motorolla battery pack (cel phone)

4 - "lone" NiMH cell from a pack of five

5 - four NiCad cells from another Motorolla battery pack

6 - original Motorolla battery pack

7 - same pack mentioned above without cover

I added some extra information to the original post at the time I wrote it (it's necessary to search the Forum Archives to find it) but they refer mostly to battery size and capacity. As mentioned by David Smith and Raymond del Tondo (these guys know what they say, believe me!) it's necessary to keep in mind that other possibilities exist and batteries with too high capacity demand longer (somehow longer...) charge time.

I think the image helps giving an idea about what can be done. If not, I'll dig Forum Archives and try to find the original post, O.K.?

Success!

Luiz (Brazil)

Edited: 27 Feb 2004, 11:03 p.m.

[Vassilis Prevelakis]

Please note that there are two arrangements of cells inside
the packs:

a)       +------+ +------+

     (-) |       >|       >|

         +------+ +------+ |

                           |

          +------+ +------+|

     (+) <       |<       ||

          +------+ +------+

b)      +------+ +------+

       ||       >|       >|

       |+------+ +------+ |

       |                  |

       | +------+ +------+|

       |<       |<       ||

         +------+ +------+

              (-) (+)

In the second arrangement you have to be VERY careful
to add insulation so that the lower two cells do not come into contact. If they do, you'll have fireworks.

For these packs I usually add a fuse instead of a metal
contact on either the left or right side of the pack. In this way if you do get a short, the fuse will blow protecting
the pack and calculator.

**vp

[David Smith]

The cells are sub-C nicad cells. Just take your old pack to any good battery store (Batteries Plus, Batteries, Etc) and they will slice it open and install new cells. Likely cost is $20-$30. Or Mark Hoskins will build you a nice one. See seller "WATERHOSKO" on Ebay.

[Raymond Del Tondo]

The Panasonic P-170 SCR cells are also suitable.
They've 1700 mAh at 1,2V.

Stronger cells than these don't make sense, because the charger should have the chance to charge them in a reasonable amount of time;-)

Regards,

Raymond

[David Smith]

Actually higher capacity cells make a LOT of sense. The HP97, etc charge the cells with a fairly high current. This can lead to heating and overcharging if you leave the machine plugged in a lot. Higher capacity cells would charge at a lower C/x rate and generate less heat and will last longer.

[Raymond Del Tondo]

Ok, that's a point.

Maybe the 97 charging circuit is slightly different to that of the 82161A tape drive, I don't know. At least with my 82161A, the P-170 cells don't get very warm, even after a whole day with the charger plugged. However, I don't use these units on a whole work day basis, so the batteries get removed and stored after use, until next time a few months later;-)

Raymond

[Jim Chumbley]

I have bought several from a gentleman who advertises on eBay. His name is waterhosko. His work is exquisite, and you might want to check with him.
Regards,
Jim Chumbley