Amdek video S-500

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Amdek video S-500

A little tangential to Apple IIs, but related.  I have an Amdek Video S500 Amber CRT  (always wanted one as a kid in the '80s).

It "works", but the image is soooooooo faded.  Even with brightness and contrast turned up full, the image will be there for maybe 30 seconds, but very dim and then fade away.

Anyone ever fixed a CRT?  Based on some Googling,  I am suspecting the fly back transformer (is that the right name)?

I have opened it up and looked around. Nothing glaringly wrong.  I have not gone as far as to ground/de-energize the CRT and start pulling wires (yes, I know, there is dangerous voltage.  I was also hit by lightning when in the Army, soooooo I think I'm indestructable.  ;-)    )

Thoughts?

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Joined: Jun 18 2010 - 13:54
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It could be the flyback. You

It could be the flyback. You'd need a HV probe to measure the actual anode voltage under the suction cup on the CRT (dange Will Robinson!). It could also be that the cathode (heater element) is also weak; there are CRT rejuvinators out there that might help temporarily. But it's worth finding out what the real issue is.

 

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Last seen: 3 weeks 1 day ago
Joined: Aug 4 2020 - 12:06
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Thanks

Yeah.  This is really out of my experience zone.  My Dad was an EE who had a lot of experience with CRTs.   I wish he was still with us to call and get advice or help.

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Joined: Aug 4 2015 - 14:30
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YouTube Adrian's Digital Basement

Not exactly a solution to your problem, but I recently saw a youtube video about improving an Amdek monitor.

https://www.youtube.com/watch?v=ehyPD7sULG0

 

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