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fedemail · 05-09-2023, 04:59 PM

Hello everyone, it may be unusual but i am in a weird situation and maybe this forum could have some advice for me.
I just bought a collection of old calculators and pcs. this includes a dozen of HP (9810a, 9830a, 9845a and b, 9100b etc) and some other brands like olivetti, wang, singer, friden and various gadgets, plotters and spare parts. Problem is, i have no knowledge at all to test/try them. I think i can handle the olivettis and the handheld ones but surely not the 1970s pc machines. These items will be for sale later but i will have to test them to describe them at best.
heres my questions, first of all, they surely have been stored and unused for years, is it safe to turn them on or it may cause damages? Is it possible for a total neophite to quickly understand how to turn them on and test the basic functions? also, some of them have monitors installed, some have not, do they need specific ones? should i just sell them as untested or the working/not working value difference is too much to ignore?
Sorry if this is out of place in here but i'm in Italy and these machines were not that much common here, i found nobody able to help me and i am trying all i can.
Thanks in advance and sorry again if this is in the wrong place.

Massimo Gnerucci · 05-09-2023, 06:57 PM

Let me know when you will put them for sale!
;)

fedemail · 05-09-2023, 07:02 PM

(05-09-2023 06:57 PM)Massimo Gnerucci Wrote: Let me know when you will put them for sale!

i will post that in the right section of the forum when the time will come!

Maximilian Hohmann · 05-09-2023, 07:29 PM

Hello!

(05-09-2023 04:59 PM)fedemail Wrote: I just bought a collection of old calculators and pcs. this includes a dozen of HP (9810a, 9830a, 9845a and b, 9100b etc) and some other brands like olivetti, wang, singer, friden and various gadgets, plotters and spare parts.

Congratulations... that must be enough to fill a small warehouse!

(05-09-2023 04:59 PM)fedemail Wrote: ...is it safe to turn them on or it may cause damages?

Regarding desktop computers I would think so. Often the electrolytic capacitors within the power supplies dry out which will result in poorly stabilised voltages. The calculators may not run properly but I would not expect them to get damaged.

(05-09-2023 04:59 PM)fedemail Wrote: Is it possible for a total neophite to quickly understand how to turn them on and test the basic functions?

The HP desktop calculators in your list have "hardwired" operating systems, so no need to boot from tape or disc. They either come on when you insert the plug and press the "ON" key or they are defective. About the others (Olivetti, Wang, ...) I don't really know without having seen them. If they already have something like the BIOS of later PCs with battery backed settings then it will not be easy to get them running again, at least not without spending lots of time reading manuals.

(05-09-2023 04:59 PM)fedemail Wrote: ...also, some of them have monitors installed, some have not, do they need specific ones?

Definitely. This was before standardised monitor connections and "multisync" monitors. To each calculator it's own monitor it was back then...

(05-09-2023 04:59 PM)fedemail Wrote: ... should i just sell them as untested or the working/not working value difference is too much to ignore?

There is an enormous difference in value between working and nonworking calculators. Especially large desktop calculators can even have a negative value in coutries like Germany (where I live) because you may be charged for the disposal of electronic waste. By kilogram - and these things are heavy!

(05-09-2023 04:59 PM)fedemail Wrote: Sorry if this is out of place in here but i'm in Italy and these machines were not that much common here, i found nobody able to help me and i am trying all i can.

Where in Italy are you? I just visited my mother over the last weekend (she lives in the province of Varese) and will visit her again sometime in june. If it is not too far away I will be happy to have a look at your collection and maybe there is something I can help with.

Regards
Max

HP-12C · 05-09-2023, 08:45 PM

Welcome fedemail,

It would be great to see some pictures of the instant collection you have recently acquired.

fedemail · 05-09-2023, 09:30 PM

(05-09-2023 07:29 PM)Maximilian Hohmann Wrote: Hello!

(05-09-2023 04:59 PM)fedemail Wrote: I just bought a collection of old calculators and pcs. this includes a dozen of HP (9810a, 9830a, 9845a and b, 9100b etc) and some other brands like olivetti, wang, singer, friden and various gadgets, plotters and spare parts.

Congratulations... that must be enough to fill a small warehouse!

(05-09-2023 04:59 PM)fedemail Wrote: ...is it safe to turn them on or it may cause damages?

Regarding desktop computers I would think so. Often the electrolytic capacitors within the power supplies dry out which will result in poorly stabilised voltages. The calculators may not run properly but I would not expect them to get damaged.

(05-09-2023 04:59 PM)fedemail Wrote: Is it possible for a total neophite to quickly understand how to turn them on and test the basic functions?

The HP desktop calculators in your list have "hardwired" operating systems, so no need to boot from tape or disc. They either come on when you insert the plug and press the "ON" key or they are defective. About the others (Olivetti, Wang, ...) I don't really know without having seen them. If they already have something like the BIOS of later PCs with battery backed settings then it will not be easy to get them running again, at least not without spending lots of time reading manuals.

(05-09-2023 04:59 PM)fedemail Wrote: ...also, some of them have monitors installed, some have not, do they need specific ones?

Definitely. This was before standardised monitor connections and "multisync" monitors. To each calculator it's own monitor it was back then...

(05-09-2023 04:59 PM)fedemail Wrote: ... should i just sell them as untested or the working/not working value difference is too much to ignore?

There is an enormous difference in value between working and nonworking calculators. Especially large desktop calculators can even have a negative value in coutries like Germany (where I live) because you may be charged for the disposal of electronic waste. By kilogram - and these things are heavy!

(05-09-2023 04:59 PM)fedemail Wrote: Sorry if this is out of place in here but i'm in Italy and these machines were not that much common here, i found nobody able to help me and i am trying all i can.

Where in Italy are you? I just visited my mother over the last weekend (she lives in the province of Varese) and will visit her again sometime in june. If it is not too far away I will be happy to have a look at your collection and maybe there is something I can help with.

Regards
Max

Thanks a lot! i will definitely test the monitor included ones. Actually, i think they kinda all of them have some sort of monitor or display so i guess they are more calculators than actual pcs? models like 9810a i tought they mounted some monitor on top but i see they actually have a couple lines of leds, other ones like the 9845 an also one ibm 51something have their small monitors attached. this may be simpler than i tought! i can handle a capacitor explosion, been there done that. Im not that far away from Varese, 3 hours top.

fedemail · 05-09-2023, 09:37 PM

here's a couple of those bad boys, the ibm i was talking about and a nice HP

[Image: 342518964-620691023290807-6945966566473760921-n.jpg]

[Image: 342488301-140785952158903-6404728750802980792-n.jpg]

also, about the Wang, it is a weird one, it has some big metallic boxes and i think a calculator looking device, ill take a look at that one soon

HP-12C · 05-10-2023, 07:17 AM

That looks a nice 9810A, you really don't see these for sale in nice cosmetic condition like this very often, nice finds!

Martin Hepperle · 05-10-2023, 12:34 PM

Concerning the HP desktop calculators line 9845/9825 etc. I would not advise to simply switch them on.

Some of them have power supplies which have a tendency to fail and then overvoltage would destroy the rest of the machine. Especially the 9825 have this problem.

Generally one should always test the power supply of such old systems outside of these machines to make sure they work as advertised.
This means removing the power supply, adding a load to it and then making tests.

If this is not possible, removing all internal and add-on boards and then powering on to measure voltages would be a compromise option to minimize the risk.

Martin

fedemail · 05-10-2023, 02:17 PM

(05-10-2023 12:34 PM)Martin Hepperle Wrote: Concerning the HP desktop calculators line 9845/9825 etc. I would not advise to simply switch them on.

Some of them have power supplies which have a tendency to fail and then overvoltage would destroy the rest of the machine. Especially the 9825 have this problem.

Generally one should always test the power supply of such old systems outside of these machines to make sure they work as advertised.
This means removing the power supply, adding a load to it and then making tests.

If this is not possible, removing all internal and add-on boards and then powering on to measure voltages would be a compromise option to minimize the risk.

Martin

that's what i feared. it is also true that i wont be able to remove and test parts like that so i guess i will take the risk. previous owner had them revised or repaired at some poit so i hope no internal components will be in such bad shape

anetzer · (This post was last modified: 05-10-2023 04:25 PM by anetzer.)

(05-10-2023 02:17 PM)fedemail Wrote: i guess i will take the risk. previous owner had them revised or repaired at some poit so i hope no internal components will be in such bad shape

As there might be some really rare items I advise to be cautious. You might try to get into contact with the guys over at

http://www.hpmuseum.net/

They might be knowledgeable about these machines.

fedemail · 05-10-2023, 03:32 PM

(05-10-2023 03:14 PM)anetzer Wrote:
(05-10-2023 02:17 PM)fedemail Wrote: i guess i will take the risk. previous owner had them revised or repaired at some poit so i hope no internal components will be in such bad shape

As there might be some really rare items I advise to be cautious. You might try to get into contact with the guys over at

https://www.hpmuseum.org/

They might be knowledgeable about these machines.

aren't we in their websit's forum?

TallKey · 05-10-2023, 03:58 PM

(05-10-2023 03:32 PM)fedemail Wrote: aren't we in their website's forum?

That'd be a hard yes.

anetzer · 05-10-2023, 04:27 PM

(05-10-2023 03:58 PM)TallKey Wrote:
(05-10-2023 03:32 PM)fedemail Wrote: aren't we in their website's forum?

That'd be a hard yes.

My bad. I have reddened shamefully and put in the link I meant:

http://www.hpmuseum.net/