VOGONS


First post, by jasa1063

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I am in the process of acquiring this computer from a seller in Bulgaria. I have only read about Pravetz computers, but what I found so interesting about this one is that is IBM PC compatible with a 80186-8 CPU. The computer is listed as in perfect working condition. I am very anxious to get it and start playing around with it. It is listed with the following components:

2 x Seagate ST-225 MFM hard Drives
Processor 80186 8Mhz
Memory (RAM): 640KB.
Japan ISA Color Graphics Board
Chinon FZ-502 FDD
3 Controller Cards

Attached are a few pictures.

I will be posting more once I receive the computer. Any comments about this computer or what others know about it will be very appreciated.

Last edited by jasa1063 on 2023-07-01, 22:20. Edited 1 time in total.

Reply 1 of 32, by jasa1063

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A few more pictures.

Reply 2 of 32, by jasa1063

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One last picture

Reply 3 of 32, by DundyTheCroc

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Looks like you have one of the latest Pravetz 16 computers with 8MHz NEC V20 CPU (maybe 12MHz Turbo mode), so called "JUKO" MB, not sure where the video card is made, but does not look like made in Bulgaria.

Reply 4 of 32, by jasa1063

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DundyTheCroc wrote on 2023-07-01, 22:38:

Looks like you have one of the latest Pravetz 16 computers with 8MHz NEC V20 CPU (maybe 12MHz Turbo mode), so called "JUKO" MB, not sure where the video card is made, but does not look like made in Bulgaria.

The seller is K-Sys Vintage Computer Parts in Bulgaria who has 1972 sales on eBay with a 100% satisfaction rating. There is 30 day return on the computer. So if it is not what they are claiming I can at least return it.

Reply 8 of 32, by Horun

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Yes I see references to a 80186 cpu for 16/ES and also a V20 for 16ES (which is technically equal to a 80188) so there is a difference ??. Wish their was a full motherboard photo...
There are 3 "pin" types of 80186, the flat CLC type, the 68 pin PGA and a 68 pin PLC (have one somewhere, came off a special controller board).
CPU world only has the fist two, you can see the PLCC on ebay...
added: if it has a 80186 would assume it the flat CLC or PGA type like some early 6 and 8mhz 80286

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 9 of 32, by ThinkpadIL

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Horun wrote on 2023-07-02, 00:25:

Yes I see references to a 80186 cpu for 16/ES and also a V20 for 16ES (which is technically equal to a 80188) so there is a difference ??. Wish their was a full motherboard photo...
There are 3 "pin" types of 80186, the flat LCC type, the 68 pin PGA and a 68 pin PLCC (have one somewhere, came off a special controller board).
CPU world only has the fist two, you can see the PLCC on ebay...

There are chances that it is actually a i8088-2 CPU

Reply 10 of 32, by jasa1063

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I messaged the seller on eBay for further clarification, but either way it should still be a pretty cool computer to have given the history of the company.

Reply 11 of 32, by ThinkpadIL

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From the bulgarian forum (translated by Google):

"JUKO and the Bulgarian version CPU-12 is used in Pravetz 16T (Turbo). It has a NEC v20 processor. The box is like the 1839ES, but under the Pravetz logo the inscription "EC 1839" is missing."

If you'll take a look, you'll see it's written "CPU-12" on your motherboard and "EC-1839" is missing under Pravetz logo, so it looks like you've bought a Pravetz-16T version.

Reply 12 of 32, by ThinkpadIL

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Here are Pravetz-16T images:

Reply 13 of 32, by Horun

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jasa1063 wrote on 2023-07-02, 00:40:

I messaged the seller on eBay for further clarification, but either way it should still be a pretty cool computer to have given the history of the company.

The two ST225 if working proper and tested good are worth about $100 each (USD$), so not sure what you paid but the parts could easily be worth the total....
And yes if it all work good then worth it if you wanted a fully working advanced XT.

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 14 of 32, by ThinkpadIL

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Horun wrote on 2023-07-02, 02:02:
jasa1063 wrote on 2023-07-02, 00:40:

I messaged the seller on eBay for further clarification, but either way it should still be a pretty cool computer to have given the history of the company.

The two ST225 if working proper and tested good are worth about $100 each (USD$), so not sure what you paid but the parts could easily be worth the total....
And yes if it all work good then worth it if you wanted a fully working advanced XT.

I understand it was that lot:

https://www.ebay.com/itm/175067641493

Reply 15 of 32, by ThinkpadIL

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And now for something completely different:

Another interesting IBM PC XT clone:

Elektronika MS1502 (Электроника МС1502)

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This one uses КМ1810ВМ88 CPU, a soviet i8088 clone. It is the only IBM PC XT clone I know about that has cassette port.

Here is the article in russian about this machine:

https://habr.com/ru/articles/531364/

Reply 16 of 32, by Jo22

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^Awesome little something! It has CGA-ish graphics with 50 Hz ? And a monitor program in ROM ? Cool. 🙂

It's so weird that this design feels kind of familiar/rational, since I'm note even from the east.
The datasette port at 1200 Baud reminds me of my Sharp MZ-700 from my childhood, too, btw.

The unconventional graphics circuit makes me wonder if it has additional features.
Normal IBM CGA has 16 KB, but its frame buffer area is mirrored/duplicated (occupying 32 KB).

So I wonder if it's the same case here or if the PC can use higher resolutions/other modes.
In theory, for example, real IBM CGA could do 640x200 in 4 colours if its address decoding circuit was complete/fine.

Anyway, I don't mean to spam this thread.
I'm just fascinated by this little PC. The hacked TV sets are beautiful, too.
Converting TVs into video monitors is so 70s! 😃❤️

Edit: The first PC is cool, too. I like the "engine hood" of the chassis.
If needed, I believe I can provide a V20 compatible BIOS.

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 17 of 32, by jasa1063

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The seller got back to me and the computer was in fact manufactured in Bulgaria which is the main thing I wanted to know. The CPU is most likely a NEC V20, but if it is an 8088-2, I can just swap that out for a V20.

Reply 18 of 32, by jasa1063

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ThinkpadIL wrote on 2023-07-02, 05:16:
Horun wrote on 2023-07-02, 02:02:
jasa1063 wrote on 2023-07-02, 00:40:

I messaged the seller on eBay for further clarification, but either way it should still be a pretty cool computer to have given the history of the company.

The two ST225 if working proper and tested good are worth about $100 each (USD$), so not sure what you paid but the parts could easily be worth the total....
And yes if it all work good then worth it if you wanted a fully working advanced XT.

I understand it was that lot:

https://www.ebay.com/itm/175067641493

You are correct, that was the eBay listing.

Reply 19 of 32, by jasa1063

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ThinkpadIL wrote on 2023-07-02, 05:16:
Horun wrote on 2023-07-02, 02:02:
jasa1063 wrote on 2023-07-02, 00:40:

I messaged the seller on eBay for further clarification, but either way it should still be a pretty cool computer to have given the history of the company.

The two ST225 if working proper and tested good are worth about $100 each (USD$), so not sure what you paid but the parts could easily be worth the total....
And yes if it all work good then worth it if you wanted a fully working advanced XT.

I understand it was that lot:

https://www.ebay.com/itm/175067641493

You are correct, that was the eBay listing.