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  #61  
Old 11-24-2013, 02:17 PM
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One question, just need to know where to set the dial pointer.

With the control turned completely counterclockwise, where should the pointer be at?
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  #62  
Old 11-24-2013, 02:27 PM
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The middle of '13'. That reminds me that have some tuner issues. I tune in channel #4 around the '3' and can;t get channel #3 at all. I figure a LO trimmer needs to be adjusted.
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  #63  
Old 11-25-2013, 10:42 AM
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It's coming along nicely, Bob. If you want to use the test CRT, I wouldn't worry about removing the focus coil from the yoke assembly. It was pretty easy to get the coil back to where it needed to be after I replaced mine. You could probably mark the spring-loaded screws to streamline the process.
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  #64  
Old 11-25-2013, 12:32 PM
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Quote:
Originally Posted by bandersen View Post
The focus is terrible because the focus coil messes up the self focusing 8XP4 test CRT.
As IsthmusTV noted, temporarily removing the focus coil from the yoke gives a nice sharp picture with an 8XP4.

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  #65  
Old 11-25-2013, 12:35 PM
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Wouldn't it just be easier after recapping and all the tests done, to put the chassis back in the cabinet and use the set's picture tube? I mean I can see doing this if you run into issues at that point, but doing all of this to me seems like a lot of added work.
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  #66  
Old 11-25-2013, 02:02 PM
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I'm on the electrolytics in my RA-113 right now. I'm doing them one-at-a-time, and reinstalling the chassis enough to hook up the CRT and speaker after each part group is replaced. So far, so good.

On these sets, we are lucky that the chassis is designed to be removed from the set easily, and has that nice big opening in the frame for repairs. Many sets have NO help for us.
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  #67  
Old 11-25-2013, 02:25 PM
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I went ahead and removed the focus coil which took care of the focus issues. Occasionally, I get a little tearing but it's certainly watchable.
I can't push the yoke all the way into the CRT bell though so it's not filling the screen.


Now as for sound I switched, to using a BT modulator set to channel 5 for an RF source and finally got some good strong sound.
Only problem is that it was miles off from the video. So much so that the screen is blank when I have sound. I tried yet another brand of modulator with similar results.

So much as I'd like to avoid it, I'm going to attempt an alignment - at least on the sound. The alignment instructions in the Dumont and Rider service info and rather complex and involve clipping pins off tubes!

Perhaps the Sams alignment procedure is a bit easier. Does anyone have a scan ?
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Last edited by bandersen; 11-25-2013 at 02:50 PM.
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  #68  
Old 11-25-2013, 02:57 PM
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Forgive the format, but here they are
Attached Images
File Type: jpg alignment1.jpg (91.2 KB, 22 views)
File Type: jpg alignment2.jpg (88.5 KB, 16 views)
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  #69  
Old 11-25-2013, 02:59 PM
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Last edited by old_coot88; 11-25-2013 at 03:04 PM. Reason: Question answered by prior post
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  #70  
Old 11-25-2013, 03:02 PM
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I have a PDF of the SAMS for the RA113. Can email to you.
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  #71  
Old 11-25-2013, 03:31 PM
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Thanks guys. I was struggling with numerous differences between the Riders and my set - even the tube lineup is somewhat different. The Sams appears to be a much better match.

They also specify using a clipped 6AK5 though so I guess I'll just sacrifice one. Not exactly the rarest of tubes anyway.
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  #72  
Old 11-25-2013, 04:44 PM
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Quote:
Originally Posted by bandersen View Post
I went ahead and removed the focus coil which took care of the focus issues.
I'd keep the focus coil if it's being used as a power supply choke. Add extending wires to the coil and mount it at some distant point (away from the CRT) in the cabinet, maybe near the bottom back. So it's available if you or a subsequent owner wants to use it on another CRT.
Quote:
Originally Posted by bandersen View Post
Now as for sound I switched, to using a BT modulator set to channel 5 for an RF source and finally got some good strong sound.
Only problem is that it was miles off from the video. ...

So much as I'd like to avoid it, I'm going to attempt an alignment - at least on the sound.
Is this a set with an independent sound IF, and not an intercarrier set? You might be able to "walk" the sound IF alignment to the frequency needed to get good sound when a good picture is tuned in. Note the direction you need to leave good sound towards a good picture, and put it back to good sound, and adjust it again back to the direction for good picture, but not completely losing the sound, and tweak the sound IF trimmers to get good sound. Repeat until you are where the good picture is tuned. Then adjust the ratio detector or such to get the DC bias is correct.
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  #73  
Old 11-25-2013, 05:02 PM
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I meant I just removed it from the neck of the CRT - it's still connected electrically. It's not used as a choke though. They have two dedicated chokes mounted under the chassis for the power supply.

Yes, it's split carrier sound. I'm going to jump right the sound alignment portion. If that doesn't work out, I'll start at the beginning.
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  #74  
Old 11-25-2013, 05:05 PM
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How are you guys feeding a signal into these DUmonts sets ? They have what looks like an RCA jack which I think is around 75 ohms impedance. All I have handy is a standard composite video cable and an RCA to F converter at the other end for the RF modulator. It works OK, but I'm sure there's a better way to do it.

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Last edited by bandersen; 11-25-2013 at 05:11 PM.
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  #75  
Old 11-26-2013, 08:41 AM
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Quote:
Originally Posted by bandersen View Post
How are you guys feeding a signal into these DUmonts sets ? They have what looks like an RCA jack which I think is around 75 ohms impedance. All I have handy is a standard composite video cable and an RCA to F converter at the other end for the RF modulator. It works OK, but I'm sure there's a better way to do it.
I was lucky to have a male "RCA" to female "F" adaptor that I acquired at some point over the years, so I use that. I don't think I have another one, but I'll check. If I do, you're welcome to it.

The picture looks quite good. I hope the sound alignment goes well. Mine was close enough that I just tweaked it a little by ear.

-Clark
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