u/BadOk3617

While looking for some M3 x 25mm bolts I came across this.

I never did find the bolts.

Here's the LED version, and precursor to the TI LCD Programmer.

And I was wrong, the TI Programmer (both versions) appears to have come out around five to seven years earlier than the HP-16C.

And unless I'm missing something, it doesn't appear to convert to binary. That seems like an oversight...

I just checked the manual and I guess not. The HP-16C can breathe a sigh of relief I suppose. :)

Which would also explain what the blue text around the hexadecimal keys is for. DIY binary conversion! :)

It's got the BP-8 battery pack with NiCads since it's rechargeable. And of course it leaked.

That's not going back in there. I'll remove the batteries from the BP-8, clean it, and store it inside a baggy. If I want to use it I'll pop in a nine volt battery.

Nice little TI-73. Still showing a result from who knows how long ago.

My new National Semiconductor "Mathematician" arrived today, and despite being a bit grungy, works nicely. I'll need to replace the battery pad in the battery compartment to prevent the battery from shorting out the board, and the On/Off switch needs lubrication or replacement. And a new 9 volt battery connector would be a plus.

And came complete with a sticker!

So I bought this Sharp PC-1500 awhile back, knowing from outset that it was non-functional (the price was right). Yesterday I decided to see what was up with it, and when I opened it up I found a veritable mother lode of bodge wires.

Does anyone recognize this mod and know the purpose of it? And does anyone have a link to schematics for the PC-1500, PC-1500A, and the PC-1600K?

Thanks!

I'm posting this in the hopes that it may save a Fadal user from having to replace their display.

I got a call from one of my friends who said that the display on his Fadal VMC20 had stopped working.

We took the display out and I measured the voltage at the output of the power supply brick the powered the display (a laptop power supply by the looks of it). No voltage at the DC jack.

In the interest of being thorough, we measured the continuity from the Molex connector to the PC style plug (IEC C13).

There was no continuity on any of the pins of the Molex to the pins on the plug. Kinda weird. Actually, way beyond weird.

After cutting the cable apart, the wires simply broke apart. In the first photo, the blue and ground broke apart after I had removed the shrink tubing. In the second, the blue or the ground broke, while the other one pulled off of its wires. Either most of them had broken at that spot (most likely), or that's all that was in the wire. In any case, the wires broke where the sheathing had been cut for removal.

This damage happened on a cable that hasn't moved in over 30 years.

We plugged in a new PC computer cord into the power supply and the display started up for us.

So before you buy a new display, check this first. Hope this helps. :)

Always nice when they work. Especially when the batteries were left in like this one.

I'm going to have to take it apart and clean it, but it looks like any damage was limited to the rusty screw on the bottom and the manual sopped up quite a bit of alkaline juice.

But it should clean up fine and be all right.

Pretty close to perfect condition. Shown with the adapter plugged in, and it works off of a 9 volt battery as well.

Hoping for the best anyway.

Pic #1 I knew that this one was going to have some problems as the seller listed it as a parts calculator, and the blue corrosion on the charging jack pretty much told the story.

Pic #2 The back cover was hot glued down. I was expecting that. And I darn near ruined it getting the cover off.

Pic #3 Looks worse than it really was. I can't see any trace damage, which is amazing in itself.

Pic #4 When I finally got the battery pack out it sent the crud flying.

Pic #5 Getting its first vinegar bath.

Pic #6 All cleaned up, mostly dry (after the vinegar bath came the rinse, and then a quick dip into 91% IPA to dilute the remaining water with alcohol. Let the alcohol evaporate (outdoors) and you are left with very little water.

Kinda hard to tell in this photo but the corners of the board are held down by melted plastic. Sort of an ad-hoc heat staking. Also note the unused octal IC footprint. It's been a minute since I've seen one of those. :)

And the wire that goes from the top of the calculator to the bottom I'm guessing is nichrome wire, and it's being used to limit the charging current to the battery pack (or was since the battery pack is gone).

Pic #7 All cleaned up and ready for the space heater. Still a bit most in this pic, but it spent the night getting dried out in front of a space heater and looks as good as new (cosmetically anyway).

Pic #8 The interior all cleaned up and dried out. You can see where the corners of the board have been melted to hold in the board.

Pic #9 Looks pretty good. :)

Looks like I'll have to make cards for it and find a manual too. But it's in great shape, and it counts as a hit on the bucket list.

Pretty little thing. I'm usually not one for converters, but the red LEDs beckoned me with their siren, umm, blinking. Yeah, that was it.

Not pristine, but not bad either.

So here's my first Doorzo haul, the "Good" part is that it came in packaged very nicely, and compactly. No wasted space and nothing rattling around. The magnetic cards for my HP-67 came in slipped inside of a card stock holder that Doorzo made for me. Thanks!

As for the "Bad", Doorzo charged me ¥6,115 to ship my package to the USA, and the very next day asked for an additional ¥10,378 for some sort of secondary charge. It wasn't clear what the additional amount was for.

I responded with "Either remove the secondary charge and ship my package as agreed upon, or refund the ¥6,115 that I spent on shipping and dispose of the items as you see fit." The next day I got shipping conformation and we'll chalk it up to a misunderstanding.

The "Perplexing" thing was finding out how to request battery disposal. I even put in a support ticket and never did get a satisfactory answer. I finally just asked them to ship it and I hoped that there would be no problems. I still don't get why it has to be such a hurdle. The lag between me asking for support, and them ignoring or giving me the wrong answer added three days to the delivery (all the while accusing me of dropping the ball in the dashboard).

Because I didn't know how well this was going to work out for me, I intentionally picked some cheap & plentiful items in the event that something bad happened (battery removal is an ongoing issue for a calculator/electronic gizmo collector). This is something that I suggest any newbie to any proxy should do.

So how would I rate Doorzo? I'll give them a C+ to a B-. I'll use them again.

I'm definitely happy with the care that they took with my items. The issue of the overcharge will probably remain a mystery, and hopefully never repeated. The battery removal process will have to be explained to me in small words and short sentences I suppose.

And an additional item that was included as a bonus from Doorzo:

"As a bonus, we’re including a SHARP electronic dictionary PA-840 that hasn’t been tested due to depleted batteries."

So that was nice of them! :)

I found this customized HP-12C the other day and picked it up because it was a bit unique (unique to me at least).

I'm assuming that there was a program to be loaded to get the additional features, but I don't have it.

Can anyone shed some light on it? Thanks!

The pictures of the two backs show that the calculator from the backside is a bog-standard HP-12C. The top one being the Chary, and the bottom one a regular 12C.