9810 question and offer

[Tony Duell]

(02-23-2014 04:32 AM)dramsey Wrote:  Well, my new 9810 is now 100% completely functional.

Excellent, even if you did it in a way that I do not approve of!

(02-23-2014 04:32 AM)dramsey Wrote:  Rebuilding the card reader was easy enough-- it's much easier to work on the 9810/20 readers than it is to work on a 65/67/97 reader. I used Katie's method since I have a huge bag of the proper O-rings. I did have to steal the drive O-ring off my existing 9180 since I only had one of those (but I've order more of them, just in case.)

The HP9810/20 card reader is a lot larger and thus a lot less fiddly to work on than
the ones in the handhelds, but I find it takes me longer because I do make the new
roller hub. The reason I do that is that I am worried the new O-rings could slip sideways on the original hub, there is nothing to hold them. By turning a hub with a couple of grooves in it, I know the O-rings will stay in place.

(02-23-2014 04:32 AM)dramsey Wrote:  My original 9810's printer platen had disintegrated into a mess of gooey tar. I have it mostly disassembled but eventually gave up working on it; I was never able to figure out how to remove all the tar from the delicate rubber paper advance belts (are there any modern parts that could replace these?) and the parts still reside in various plastic bags. However, the associated controller board didn't have the stuck transistor my new controller board did, so plugging it into the new calc resulted in a fully functional printer.

Yes, the printer platens decay too. I use the method suggested by Katie et al, that is to use 3M Cold Shrink. The smallest size kit of that contains a pair of rubber sleeves and the Cold Shrink itself. You force the rubber sleeves onto the original spindle, then put the Cold Shrink over it -- 2 layers. The only hard part is trimming the new roller to length.

(02-23-2014 04:32 AM)dramsey Wrote:  (Somewhere in England, Tony is shaking his head...)

Hmm... That's the polite way of putting it.

(02-23-2014 04:32 AM)dramsey Wrote:  -- One mostly functional 9810 (a couple of dead segments in the bottom line of the display; card reader needs new drive O-ring, unlikely ever to have a working printer)

The only part of the printer you can't really do anything about if it fails is the printhead. Every other part can either be obtained or repaired. So don't give up on this one. Apart from the gooey platen, what other problems does it have?

(02-23-2014 04:32 AM)dramsey Wrote:  -- One parts 9810 (doesn't really work at all)

Again, there are very few HP9810 problems that can't be fixed. ROM failure is the main one, actually. All other chips were standard at the time, although some are going to be hard to get now (the RAMs, and some of the more obscure TTL parts). And IMHO debugging one of these machines is fun!

(02-23-2014 04:32 AM)dramsey Wrote:  It's not even my favorite HP. But maybe I can bring it to wherever we have the meeting this year.

It is one of my favourite HP's. I think I'll put the HP9830 first, then the HP9100, then this one. It's a very interesting design.