Retro Nora💾
@RetroNora7734
Professional 'trash' collector. With focus on computers from former Eastern Bloc - mostly on these from Polish Peoples Republic.
I guess it's time to make a proper introduction of my IBM PC XT. Or as I like to call it a 5150 wanna-be, would call it 5155, but it's already taken. Got it in september 2022 as my BDay gift. Was a bit overpriced but well. It was my dream to have one.
And this confirms that my A5120 has polish char set. So maybe I should call it A5120p.
Since now I have working K7222 monitor so let's check what's going on. For Robotron 1715 there is no video output, for A5120 there is garbage on screen.
Since the monitors from PR Poland are kinda sorted out let's go back to UHA78 and monitors from DDR. This time result is very good. There is no sparking from new HV coil, the voltage measured at the cap is 8,8 kV. The result is better then in MC80.
With the Biazet TMP201 bought for it's trafo turned out not to be needed for parts now I have one more TV set. The red Neptun 150 monitor is missing a CRT now, but with these being more popular then Unimor 4902 I am fine with that.
I have bought my second Neptun monitor for parts but did not expect that will need them so soon.
The potentiometer glows because: The CRT got a weak vacuum and two grid voltages are shorting via the CRT, so they 'meet' at that potentiometer. *Sigh*
Glowtentiometer?
I'll just replace the driving transistor and HV transformer and it will just work - right? Wrong. It will fry focus potentiometer. *Sigh*
I have just noticed the chassis is connected to the case. So the *plastic* case is *grounded*.
But it turns out this Neptun is not an ordinary one. After I arrived home I noticed it's back. Not only it has low serial number and comes from 1980 - first year of production. It is also a export version for W. Germany branded by HGS Elektronic. Didn't know such version exists
Today was a flea market day. Got three amazing stuff. -Ameprod TVG-10 one of few models of Pong clone made in PR Poland. -Philips TV from 1974 (for 4€!), -and 'just' Neptun TV for parts.
Today was a flea market day. Got three amazing stuff. -Ameprod TVG-10 one of few models of Pong clone made in PR Poland. -Philips TV from 1974 (for 4€!), -and 'just' Neptun TV for parts.
How to fix any monochrome monitor made in Polish People's Republic: Find out on what model of BW TV set it is based, buy that TV for cheap. You're done.
The concentration of UHA78 is my workshop is so high that other trafos started to burn.
