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#1
03-17-2013, 04:24 PM
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My new predicta
I just got home and as soon as I got out of the car I gave it a much more detailed look and I saw modern capacitors underneath the set so I pulled out the chassis and someone replaced all if the caps underneath but not on the board!!
On the pc board everything was original and there were two black beauties that were cracked. After all if this I decided since most if the components had been replaced it would be reasonably safe to power it up I got good sound but it was a little weak and no raster I suspect a cold joint in a tube socket since I saw a raster when it was in the mall but I didn'ta leave it on long enough to warm up  .ImageUploadedByTapatalk1363555453.569296.jpg 
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Lebe dein leben für dich selbst **Searching for any all tube or hybrid or color portable sets would consider some early solid state color too** 
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#2
03-17-2013, 09:44 PM
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Congrats on the new Predicta!
Check out Bob's series of videos on the Predicta Holiday. A LOT of good tips in there and how to deal with the early PCB's and the cuplates. http://www.youtube.com/playlist?list...2y62xYCp5PgZx_
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#4
03-18-2013, 02:56 AM
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Wow, not only a great price but so much work already done for you!!
Makes me wonder where the set came from... it might be interesting if you get a chance to talk to the dealer and ask them the backstory.
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#5
03-18-2013, 07:42 AM
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I would like to know its story and why the person stopped working on it. Hopefully they dident discover that some unobtainun part wasn't fried like the flyback or CRT
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| Audiokarma |
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#6
03-18-2013, 10:52 AM
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Looks like it has the original thermistor and filament dropping power resistor. Often one or both of those are bad.
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#7
03-18-2013, 10:56 AM
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The thermisistor is good but I don't know what the dropping resistor shops measure at on my ohm meter?
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#8
03-18-2013, 11:00 AM
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Also what should the voltage readings be on the pins of the CRT?
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#9
03-18-2013, 12:38 PM
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You can download the Sams service info for free here: http://www.earlytelevision.org/tv_sc...s_postwar.html
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#10
03-18-2013, 12:44 PM
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Thanks! That will be a lot of help when I get into the set more.
So do you guys think when I pull the PCB I should rebuld all of the networks that seem to go bad frequently and all of the resistors as a precaution?
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| Audiokarma |
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#11
03-18-2013, 02:22 PM
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I wouldn't rebuild the networks unless you really want the practice. If you'd like to tackle one, which in my opinion is the worst offender and also the simplest to build, tackle the vertical integrator, which is the short 4 pin network next to the vertical output.
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#13
03-18-2013, 03:05 PM
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Quote:
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#14
03-18-2013, 03:36 PM
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Yes, I did at some point in the videos. Some are just encapsulated discrete components (carbon comp resistors, ceramic caps, etc). Other networks (vertical integrator) are made from carbon and metal deposited on a ceramic substrate.
Here's my restoration thread in case you haven't read it yet: http://www.videokarma.org/showthread.php?t=255328
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#15
03-18-2013, 05:02 PM
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If the video output tube (6aw8a) is gassy or dead would that cause the screen to be completely dark I just looked at this tube with the set on and it is very purple inside when on so is the horizontal output tube.
I have determined there is HV but I don't have a probe to measure the exact voltage but I can get a 1/2 centimeter spark to the housing of the flyback transformer.
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Linear Mode
