Humdinger
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- Sep 22, 2012
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Made an interesting discovery today. Was in the process of rebuilding several 4600 chassies and after throwing the latest one in the test machine today, I had a monumental sync and hula issue accompanied by an apparent flyback whine. Swapped the cards around and still had the exact issue, so I ruled them out. Noticed that the activity on the screen kept perfect time and intensity with the whine.
Got on trusty KLOV and searched for "4600 flyback whine" and found an interesting tip involving sticking a toothpick down into the flyback's core sleeve to eliminate the noise. Some folks had had good results with that, but the logic behind it had me curious: what would cause the core to loosen enough to (I presume) "oscillate"(?) badly enough to a) cause the whine and b) cause the screen/sync interference?
Then I just happened to notice that a threaded shaft with a tiny nut on the end was trying to slide out of the flyback. Further examination revealed that one side of the flyback's "keeper" clip/retainer thingy that runs up one side and back down through the flyback had corroded and broken off. The only reason I saw this was because the bundle of wires that obscures this shaft (and only allows it to slide out if moved) was originally held fast with a zip tie, and I had cut that tie off earlier. This allowed the wire bundle to move out of the way and then the broken shaft slid right out.
Now say the following in the inflection of the narrator on The Curse of Oak Island: "A broken flyback core retainer? Could this cause the flybacks in thousands of 4600's to make a whiney noise and cause a person to erroneously believe that his flyback was failing? Could a new retainer fix both the noise and the sync/screen issue, thus enabling thousands of presumed-dead 4600's sitting on shelves across the nation collecting dust to come out of retirement?"
I figured that was just too easy, and that surely Entringer or Dokert or Layton or Buffett or some other monitor guru had probably figured this out long ago. But then I pulled 3 more salvage 4600 chassies off the shelf to check the retainers, and what do you know? All broken! Only one looked usable, but when I attempted to gently tighten it down on the chassis I was trying to test, it too broke under the slightest of pressure! Thanks to that, I now have no more retainers to install to see if indeed the problems disappear when the core is held fast.
I have attached a picture of 3 broken retainers. All had brown goo-like corrosion in the very spot where they snapped. It's not rust, but whatever it is must have altered the retainer's metal composition on a molecular level and weakened it internally.
Has anyone else dealt with this issue? I have never seen another post discussing this retainer thingy and I'm sure I'm gonna have to have a dozen or so made just to prove this theory of mine. I'd love to hear from you guys if you know of a better way to handle this. Or you can just tell me I'm full of poo.
Thanks in advance.
Got on trusty KLOV and searched for "4600 flyback whine" and found an interesting tip involving sticking a toothpick down into the flyback's core sleeve to eliminate the noise. Some folks had had good results with that, but the logic behind it had me curious: what would cause the core to loosen enough to (I presume) "oscillate"(?) badly enough to a) cause the whine and b) cause the screen/sync interference?
Then I just happened to notice that a threaded shaft with a tiny nut on the end was trying to slide out of the flyback. Further examination revealed that one side of the flyback's "keeper" clip/retainer thingy that runs up one side and back down through the flyback had corroded and broken off. The only reason I saw this was because the bundle of wires that obscures this shaft (and only allows it to slide out if moved) was originally held fast with a zip tie, and I had cut that tie off earlier. This allowed the wire bundle to move out of the way and then the broken shaft slid right out.
Now say the following in the inflection of the narrator on The Curse of Oak Island: "A broken flyback core retainer? Could this cause the flybacks in thousands of 4600's to make a whiney noise and cause a person to erroneously believe that his flyback was failing? Could a new retainer fix both the noise and the sync/screen issue, thus enabling thousands of presumed-dead 4600's sitting on shelves across the nation collecting dust to come out of retirement?"
I figured that was just too easy, and that surely Entringer or Dokert or Layton or Buffett or some other monitor guru had probably figured this out long ago. But then I pulled 3 more salvage 4600 chassies off the shelf to check the retainers, and what do you know? All broken! Only one looked usable, but when I attempted to gently tighten it down on the chassis I was trying to test, it too broke under the slightest of pressure! Thanks to that, I now have no more retainers to install to see if indeed the problems disappear when the core is held fast.
I have attached a picture of 3 broken retainers. All had brown goo-like corrosion in the very spot where they snapped. It's not rust, but whatever it is must have altered the retainer's metal composition on a molecular level and weakened it internally.
Thanks in advance.
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