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Star Wars upright - restoration

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Level42:
Without the BU406D you can check everything up to the BU406D's "input" (base). Everything behind the BU406D (the "Mystery can", HVT and the diode, and of course the CRT) are not powered up, so if there's a problem in that section it won't hurt the parts before the BU406D.

So, without much risk, you can measure if the 7824 and 7924 are working OK. I guess you don't have an oscilloscope (if you plan on more game restorations, this is a great tool:
http://forum.arcadecontrols.com/index.php?topic=73111.0) but if so, you can verify if the 555 is oscillating. Basically this means you have a block-wave (well kind of) on the output of the 555. This is amplified by one ore two transistors (before it reaches the "input" (base) of the BU406D.
This is all described in the Amplifone FAQ, you really need to invest some time in reading it.

The only way to really know if the HVT is dead is by using a HVT tester. But it doesn't make sense to buy one just for this. Basicaly, if everything is OK when the BU406D is not in the circuit, and things go wrong when you replace it and test again, the HVT is most likely dead. It could also be the "mystery can" but that chance is a lot slimmer.

Do you have a pic of the neck of the CRT showing what you described ?


shilmover:
I can get a pic of the neck, but in a nutshell, there is a little plastic "cup" in the middle of the male connector...  that fits in the hole in the "female" part.  and its broken...   :-[

Having said that, I checked everything and it appeared okay.  But I decided to replace some of the components anyway.  I replaced the 7824, 7924, the diodes, the resistors, the BU406D.  I turned everything on but did not see a neck glow, but stuck my head around the front any way and guess what...  Its working!!!  :cheers:  I rechecked what I did when I replaced the flyback and I believe I had the voltage set too high (R17).

I have a nice, beautiful Amplifone monitor... for now...  Hopefully it will stay running.

shilmover:
Quick question... 

My SW Yoke "pulls" to the right...  I read in the instruction manual that its auto centering, but it definitely pulls left.  How do I center it?

shilmover:
A few more pictures...

1.  Counter, Volume control, Coin and Test Switch panel before
2.  And after
3.  The Marquee repainted....  it was in bad shape and broke when I removed the broken, rusted screws...  I had to fix it.  I also had to paint it several times to get rid of the moldy smell

shilmover:
I am thinking of re-cap'ing my AR-II board.  Any suggestions what I should replace?  Anyone have a list? (there is a local place that has almost every cap I could imagine of.

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