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  #1  
Old 08-06-2016, 09:57 PM
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Mahogany Predicta Pedestal

A friend of mine heard I restored my blonde Predicta pedestal and asked if I would restore his. He brought over this mahogany version with optional UHF tuner. The flyback looks pristine and the chassis shows no signs of ever being repaired. So here goes another...
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Old 08-06-2016, 10:03 PM
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The CRT is the 2.34v CRT and initially tested bad. I thought I was going to have to call and give my friend bad news. I decided to cook it at 3v for 4 hours and see if I could breathe life back into it. After a few hours I brought it back to the CRT tester. Emissions came up into the good section quickly. I hooked it up to a restored Predicta chassis and I was rewarded with a bright raster! Now to get my parts list together and do some cleaning..
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Old 08-09-2016, 04:05 PM
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The printed circuit board is out and I placed my capacitor order today. This board is very clean with no cold solder joints or questionable repairs. I'll start replacing out of tolerance resistors while I wait for the caps to come in.
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Old 08-10-2016, 12:56 PM
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All out of tolerance resistors have been replaced on the printed circuit board. Now awaiting my cap order to finish off the pcb.
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Old 08-10-2016, 07:33 PM
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Originally Posted by Radiotronman View Post
All out of tolerance resistors have been replaced on the printed circuit board. Now awaiting my cap order to finish off the pcb.
You forgot the really big ones...They always have a different resistance from the color code.
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Old 08-11-2016, 08:35 PM
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Funny Tom...while I'm waiting on the caps to come in, I took time to clean the case and the CRT housing with lense. The mold was very thick, but Easy Off oven spray made quick work of it.
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Old 08-12-2016, 09:30 AM
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Just wanted to tell ya I'm riding along and enjoying this thread. Keep posting your progress.

Jonathan
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Old 08-12-2016, 10:08 AM
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Originally Posted by Radiotronman View Post
Funny Tom...while I'm waiting on the caps to come in, I took time to clean the case and the CRT housing with lense. The mold was very thick, but Easy Off oven spray made quick work of it.
It's actually not mold - that's the tenite plastic decomposing. I'm afraid that it will slowly come back

I've never heard of using Easy Off to clean these. Did it cause any harm to the plastic ?
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Old 08-12-2016, 11:16 AM
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It's actually not mold - that's the tenite plastic decomposing. I'm afraid that it will slowly come back
Interesting. I wonder if it is reacting with the atmosphere to decompose.....If it is then perhaps a transparent coating (like lacquer maybe) might stabilize it long term.
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Old 08-12-2016, 11:51 AM
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I mostly used the oven off on the actual mold on the outside of the CRT case and band strap. I did use it in the lense cover, but very carefully. It cleans the plastic very clean and after minimal buffing, very shiny. Like any cleaner, always use in small amounts first before using. It works very well on plastic and wood, but don't use on Bakelite. It pretty much instantly takes the greasy dirt off of the rubber wire, with very little work. Makes the wire look like new.
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Old 08-12-2016, 11:52 AM
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Ive also found that if I keep these predictas upstairs and not in the basement, that white haze on the CRT lense does not come back. I think it all has to do with temperature and humidity.
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Old 08-12-2016, 12:28 PM
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I think coating them won't work. I've seen knobs made of similar plastic that were clear coated and the crud formed underneath causing cloudiness and the coating to start flaking off.

Yes, higher temperature and humidity do seem to accelerate the deterioration. It's been my experience that it will always start coming back. It may take months or years but haze and the stinky smell always return.
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Old 08-12-2016, 01:53 PM
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My cardboard insert that seperates the video cable from the hv, yoke and CRT filament cables fell apart when I began cleaning the wires. I found that a toilet paper roll works perfect as a replacement.
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Old 08-16-2016, 10:50 AM
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The main pcb is all recapped. Now onto the rest of the chassis.
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Old 08-16-2016, 12:42 PM
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The rest of the chassis is recapped, including all of the electrolytics. Now I need to reinstall the pcb and give it a slow power up.
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