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smiba

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About smiba

  • Birthday 01/10/1999

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  1. This is a common misconception and it totally depends on what kind of failure the CRT is experiencing. Yes, Rejuvination is not something that can be used to make a CRT last a lifetime. Once the filament degrades far enough there is just not enough emissions to show a bright picture! However it is possible there is a containment inside of the tube, causing trouble. By rejuvenating you will send a pulse through the filament, hopefully displacing whatever is causing trouble. As my issue with the CRT isn't emissions, the picture is bright, I hope there is something that gi
  2. Can you check out UG6 and UF8A as well? UG6 is responsible for the final video signal going to the CRT, although its quite possible (and likely) this fault happens at an earlier moment. I think its interesting that its just missing 2 pixels every 2 pixels though, as that is a pretty binary isuse (second digit staying low) I'm not very well known to the video circuit as its complicated and abstract due to all the generic PAL chips, I may check it out a bit more tomorrow. As for the audio check out C4's via on the negative side, it looks affected by the leaky caps. T
  3. This is what I expect to see from a bad capacitor on the vertical signal to the yoke. Its analog distortion I've sadly never touched Colour Classic board, so I can't check for you. But I'd start with the cables coming from the yoke, follow back the two cables for vertical. The capacitor that may cause this will be very close in the circuit to this, it may come after or before a coil but it shouldn't been too far into its circuitry. (It might be further "physically" on the board however) This is a Macintosh SE/30 I got in recently, this had a bad capacitor on
  4. Just to be sure, what did you replace the capacitors with? The audio circuit exists out of a bunch of caps that often leak, so I assume you replaced them. If you replaced them with an inadequate replacement this may cause audio issues. If the audio signal is affected, so may their working in different parts of the board. I think the jailbars are a seperate issue from the audio though, just for us following along, any chance you could take some high resolution shots of the video / PAL areas? In my experience corrosion or damaged traces can sometimes be easily spotted on pi
  5. I just received the CRT rejuvenator, I plan on cleaning it up first and recapping where needed. I don't have the right connector for the tube yet too, gonna have to work on that or convert one of the adapters I received with it (But preferably I would just find the right adapter) Hope to give an update in a few weeks @PotatoFi If you end up swapping the yoke please let me know if this affected or solved the issue in any way
  6. @elemenoh Thanks for all the work so far! Any chance you could export the PDFs so they're searchable? Right now the text is being stored as vectors so PDF readers can't search through them
  7. Right now I swapped the CRT and that fixed the issue. This brings us to the following conclusions: - The Motherboard, analog board and power supply are most likely fine - The CRT Board (which attaches to the back of the tube) is most likely fine And leaves us with the following possible problem causes: - The yoke is bad (wiring) on the CRT - The yoke cable is bad to the yoke of the CRT - The filament inside of the CRT is dirty - There is another unspecified issue with the electron gun of the CRT - There is an issue with my motherboard, analog bo
  8. Shipping on Mouser kills me at the moment though (€20 for a €0.50 part) The cap is unlikely to be a problem at this moment though, as a replacement tube doesn't show this issue.
  9. Thanks! I already made sure its not the CRT board, I've swapped that out and the issue persisted. The same board works fine on a different CRT (See my above post, I use the same CRT Board) The only thing I've not tried replacing is the yoke, everything else has been swapped at some point. Basically a different CRT with same internals does not show this issue (Same PCB Board too). Its only on this specific tube (and maybe the yoke, as that is the only "somewhat" removable part I haven't changed)
  10. The burned connector (Although it mostly just looks brittle?) is on the CRT that actually functions correctly... haha The calibration on both screens is really well done, so I'd rather not remove the yoke (at this point). I think I have another SE that has horrible calibration so I might steal that Yoke as it would've been needed to be calibrated either way. Is there any instruction on how to remove it? Its a fairly sensitive part so I don't want to break anything
  11. CRT swap didn't have the issue, so its either the CRT itself or the cables to it... Can anyone explain this behaviour of the CRT? I don't understand how the tube itself can cause this to happen I'll need to fix this CRT I have in it now though, as it has its molex connector killed...
  12. I'm reluctant to do so as the contacts themselves look good and nothing happens if I move it around. Also this behaviour is quite unlikely from a bad connection on the data line on the CRT or CRT board
  13. CRT board swap did not resolve the issue or chance the behaviour in any way... So its either on the motherboard, some other part on the analog board (resistor, ic, etc.) or the tube itself (which feels unlikely, as I don't understand why the electron gun would act this way)
  14. Sadly recapping the Analog board didn't show any results, horizontal image still collapses weirdly on reset and there still is bleeding/ghosting to the right. All caps (Samyoung branded) measured reasonably within spec (all capacitance values are met higher then spec, ESR was a bit up but nothing that shocked me...) I'm considering replacing the 3.9/35v bipolar with 2 regular polarized capacitors to make a bipolar (using 2x 10uF). This capacitor goes to the horizontal signal on the yoke, but I don't think its responsible for the ghosting/bleeding. Also using 2x 10uF would
  15. As there is no way for my to edit the wiki unless I "request" an account, I'll just post the details here: Analog board 820-0206-C 1 x 4700uf 16v - lead spacing 7.5mm - diameter 18mm 1 x 1000uf 16v - lead spacing 7.5mm - diameter 16mm 1 x 3.9uf 35v bipolar - lead spacing 7.5mm - diameter 16mm -- I have not found a in stock replacement for this. Looking for film capacitors but Farnell is fully out of stock 4 x 100uf 25v - lead spacing 5mm - diameter 8mm 2 x 220uf 16v - lead spacing 5mm - diameter 10mm 1 x 10uf 160v - lead spacing 5mm - diameter 10mm
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