🇺🇦 УМПК-Р (UMPK-R): Part 2 (Trying to get video output) [TCE #0545]
28Unfortunately not much progress in this video - we do power it on but haven't been able to get a proper video signal out of it yet. Discussing designing a replacement, mechanical keyboard, it looks like we would need to source an СНП58 (SNP58) style connector.
The manual (in Russian) can be found here:
https://www.patreon.com/posts/umpk-r-manual-115886138
00:00 ... Intro
04:20 ... Discussing the [УС] and [СС] modifier keys
05:10 ... Power supply pinout
07:00 ... Making up a terrible temporary power cable
09:20 ... First power on test (NOK)
11:00 ... Discussing the video output modification plans
14:42 ... Checking video signal on the oscilloscope
16:40 ... More video circuit discussions
21:15 ... More video circuit shenanigans
25:00 ... More oscilloscope fiddling
29:20 ... Something on the screen
31:00 ... More fiddling to get rubbish on the screen
33:55 ... Channel thanks & outro
From Part 1:
Here we have another "serially produced" version of the Soviet-era home brew computer Радио-86РК (Radio-86RK) based on their Intel 8080A equivalent, the КР580ВМ80А (KR580VM80A). This fellow comes from Мукачево (Mukachevo) in the Ukrainian SSR (as far as I can tell). There was a 16KByte version (УМПК-Р16) and this 32KByte version (УМПК-Р32).
It is a pretty simple machine, nicely made if we ignore the membrane keyboard with a dozen space bars. It has a four-pin socket for power in, a 5-pin DIN for cassette, RF-output for TV and a DN4612-style expansion port (СНП?).
As it's an 8080-based machine it requires ±5VDC and +12VDC.
My understanding of the special keys on the JCUKEN keyboard layout (thanks to @Mercury13kiev & @sergijtolmeros for their input!):
[ВК] = Возврат Каретки = carriage return
[ЗБ] = ЗЗабой = backspace
[СС] = Специальные символы = special characters
[ПС] = Перевод Строки = line feed
[СБР] = Сброс = reset
[УС] = Управляющие символы = control characters
[АР2] = Автоматический Режим 2 (automatic mode), or more recently Альтернативный Регистр 2 (alternate register)
[СТР] = Система Трансформации Реальности, or [CTRL]
ВКЛ = Бключить (turn ON)
Sergey's excellent reproduction of the Radio 86RK:
https://github.com/skiselev/radio-86rk
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