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  #46  
Old 04-25-2017, 11:46 AM
Tony F Tony F is offline
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Well I finally got this Predicta up and running. Thanks to El Predicta for the replacement flyback and assorted parts I needed. I found a 3.2 ohm Emerson speaker to sub for the one that was missing. I thought I would post a few pics. I still need to play with the yolk a bit. The top left side (looking at the set) seems to be pulled to the center a bit. Maybe someone could tell me what I need to play with to fix it. Also, I'm still looking for some suitable grill cloth. In case you are wondering about the messed up grill cloth. I cut a square from the top quarter of what was there for a sample. The bottom 3/4 of the grill cloth was the way I acquired the set. The networks seem to work great. I also need some reproduction gold numbers for the dial as these ones are completely worn off. I thought about using a trim piece from a princess but the "Philco" logo would be sideways as it is painted on the back.
Tony
Attached Images
File Type: jpg Predicta1.JPG (51.0 KB, 30 views)
File Type: jpg Predicta2.JPG (49.4 KB, 8 views)
File Type: jpg Predicta3.JPG (48.4 KB, 6 views)

Last edited by Tony F; 04-27-2017 at 10:41 AM.
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  #47  
Old 04-27-2017, 08:56 AM
Tony F Tony F is offline
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Could someone tell me if there is anything I can do to minimize or get rid of the retrace lines on this set ? From what I understand, it is or has something to do with the timing of shutting the gun off at the right time. It uses the 10L43 chassis and all caps and resistors have been swapped out (except for the tuner). They are pretty visible at the top 1/3 of the screen. Is there some value of a component I can play with, or is it just to be expected ?
Thanks !
Tony
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  #48  
Old 04-27-2017, 09:18 AM
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bandersen bandersen is offline
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They have a retrace suppression circuit. Looking at Sams 466-1 they pick a signal off the vertical output transformer and feed it into the brightness control. Check R26 and C27. They show a dashed line across R26 which I think means in some version it's shorted out. You might want to try shorting and unshorting that resistor.

BTW I note in your photos that the image is stretched vertically and doesn't fill horizontally ?
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  #49  
Old 04-27-2017, 01:07 PM
WISCOJIM WISCOJIM is offline
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Quote:
Originally Posted by bandersen View Post
BTW I note in your photos that the image is stretched vertically and doesn't fill horizontally ?
Wrong aspect ratio selected on a converter box?

.
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  #50  
Old 04-27-2017, 01:42 PM
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Electronic M Electronic M is offline
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Quote:
Originally Posted by Tony F View Post
Could someone tell me if there is anything I can do to minimize or get rid of the retrace lines on this set ? They are pretty visible at the top 1/3 of the screen.
Tony
Are you familiar with macrovision copy protection? It is common on DVD and VHS tapes and can cause what looks like a retrace issue on tube era sets.

IIRC Phill's old radios has a good write up on it.
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  #51  
Old 04-27-2017, 02:46 PM
Tony F Tony F is offline
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Hi, I'm playing all recordings off of my popcorn hour with a 4 GB hard drive (Cloud media) hooked up to the set, through a radio shack modulator that has channel 3 and 4. I've tried swapping aspect ratios (on the popcorn hour)16:9 > 4:3. I've tried various formats. (That is the "bars" you see on either side of the picture). If I swap to the output of my satellite receiver it will output a full width picture without the bars, but the retrace lines are still there (even with no output source). So I'm back to Bob's advice about the resistor and cap combo. I've got a little digging to do. Thanks for the help so far.
Tony
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  #52  
Old 05-16-2017, 11:40 AM
Tony F Tony F is offline
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Hi, I have a question about the vertical linearity on this set. I get lots of vertical height, the problem seems to be the width of the scan lines between the bottom half and the top half of the picture. The bottom half the lines have a lot of spacing between them, and the top half seems tighter together. If a man is standing with his waist in the middle of the screen his upper body and head is shortened up and his legs at the bottom are longer and out of proportion. The magnets on the back of the yoke only seem to have limited effect, when playing in combination with the vertical linearity control in combination with the horizontal controls. Sams shows (2) 680 ohm resistors R61 & R62 in parallel with the yoke coils. I didn't really notice them when I had the picture tube cover off. Are they located on the front of the black plastic yoke cover (where the magnets are) or are they located underneath this cover. Also, with C53 being a ceramic disc, should I think about replacing it as well ? Those would be the only resistors I hadn't replaced. All paper and electrolytics were replaced with the exception of the original ceramic disc caps. All tubes are NOS.
Thank-you
Tony
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  #53  
Old 05-16-2017, 11:48 AM
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bandersen bandersen is offline
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The resistors are under the cover, but I really don't think they will have any effect on linearity. I believe they are damping resistors to prevent ringing. I'd leave the cap alone too.

The magnets won't have much effect either. They are for centering and horizontal linearity correction.

The vertical linearity control should have a very, very noticeable effect. It also interacts with the height control so you'll need to go back and forth with adjusting them to get the best linearity at the right height.
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