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-   -   Crosley 348CP "Swing-A-View" Restoration (http://www.videokarma.org/showthread.php?t=268361)

vts1134 01-12-2017 02:10 PM

Crosley 348CP "Swing-A-View" Restoration
 
I have been working on a Crosley 348CP television for a while now. This set is called the "Swing-A-View" because of the interesting way the CRT pivots out of view when not needed and out when you are watching the set. It's a really cool set and I've not seen many others out there. I am a real sucker for large console sets so this one really caught my eye. I had previously posted two threads about it on VK. Here is the thread explaining how I found it along with three other giants http://videokarma.org/showthread.php?t=267334. And here is a thread where I asked for help with direct video injection for it http://videokarma.org/showthread.php?t=268178. I thought I'd make one thread for the remainder to share the process and more importantly to ask all of you to help push me over the top with this one. I have been terribly unmotivated lately and so tired after working all day, then coming home and dealing with two small children. At the end of the day when they are tucked into bed, the house is clean, and I've answered work email for the day I just want to sit in front of a modern TV and have a drink before going to bed :sigh:. So I'm hoping all of you can give me both the technical help and social encouragement I need to finish this beauty.

The cabinet was in fair condition and needed the help of a pro. I shipped it off to a local cabinet guy in the Pittsburgh area. He has since finished, but I've not been able to pick it up yet. Here are some before shots.

http://i1075.photobucket.com/albums/...psenwnt5k3.jpg

http://i1075.photobucket.com/albums/...psnevknsgj.jpg

http://i1075.photobucket.com/albums/...psripdcr5r.jpg

http://i1075.photobucket.com/albums/...psadaxahks.jpg

http://i1075.photobucket.com/albums/...psymy3m4no.jpg

David Roper 01-12-2017 06:35 PM

Not surprised about going the direct video route. This might be the one set (postwar anyway) that is simply unrestorable to original operation.

decojoe67 01-14-2017 12:16 PM

I enjoyed seeing this set. It has proven to be a rare one. I would say about as rare as some pre-wars. The uniqueness of it certainly makes it worth the effort to return it back to it's former glory. Good luck!

vts1134 01-16-2017 01:43 PM

This set has three seperate chassis. The "main" chassis sits on the bottom of the cabinet and houses the tuner, video and audio IF, and the deflection circuits. The "vision" chassis lives inside the swivel box at the top of the cabinet. It houses the CRT and video circuits. Then there is a radio chassis that houses the radio as well as some of the controls for the TV.

Radio chassis:

http://i1075.photobucket.com/albums/...psqh4av0ve.jpg

Top of the vision chassis with 10FP4 CRT:

http://i1075.photobucket.com/albums/...ps3vyv6agy.jpg

Main chassis:

http://i1075.photobucket.com/albums/...pselveomfz.jpg


I am about 85% of the way there with this one, I just need a gentle push to get it finished. I have recapped all three chassis and I'm down to just a few issues left to resolve.

1- The focus control is right up to the end of its adjustment in order to get a focused picture. I'm not sure where the CRT neck will fit in the focus coil when it's in the cabinet so it might not be enough adjustment.

2- The horizontal centering does not work.

3- There is an intermediate loud crackle or distortion that happens after the volume control.

4- There is an odd "zipper" interference in the video. You can see that interference here https://youtu.be/zgcznUOokvw.

I don't know which problem to tackle first.

bandersen 01-16-2017 02:03 PM

I'd go after the horizontal centering first. The 100uF electrolytic cap across it might be bad or installed backward. If so, it would likely be the source of the zipper interference too.

vts1134 01-16-2017 08:24 PM

Well...I had a few minutes to get under the set tonight. I realized I forgot to mention one more problem. I have a vertical deflection problem also. Most of the time when I power the set on the raster is very compressed vertically. I can get it to come back by wiggling a cap on the vertical osc tube. I'm sure I can find the issue there and fix it.

I was able to find the source of the "zipper" effect in the video. I have a bad cap in the horizontal oscillator. The cap in question is an 88pf cap. I had a couple of caps in parallel with a clip lead in the circuit as a temporary replacement. When I took the clip lead out and soldered the caps in place the problem disappeared. I do need a correct capacitor to replace the defective one. Does anyone have any spares?

http://i1075.photobucket.com/albums/...psdq3nncsh.jpg

Phil Nelson 01-17-2017 12:38 AM

Hey, that sounds like progress!

I would definitely encourage you to forge ahead and finish the TV. Gotta love that swiveling peekaboo screen.

I know what it's like to get bogged down in a big project. I've been tinkering with a Dumont RA-102 for months now -- far longer than it would take if I had worked on it regularly rather than sulking or looking for excuses (the holidays! the cold weather! a butterfly flapping its wings in Asia!). So, do what I say and not what I do: you'll feel great when you're all done :)

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

Radiotronman 01-17-2017 05:39 AM

I'd encourage you to finish this hard to find set too. I usually work on 2-3 sets at the same time, so when I get frustrated with one I pick up on another set already started. My dad repaired sets for years and he's often said, sometimes you've gotta stop and take a break or you'll drive yourself nuts.

vts1134 01-20-2017 12:13 PM

Quote:

Originally Posted by bandersen (Post 3176828)
I'd go after the horizontal centering first. The 100uF electrolytic cap across it might be bad or installed backward. If so, it would likely be the source of the zipper interference too.


I had a few minutes to spare last night so I looked at the horizontal centering. I tried putting a 100uf cap across the control to see if it made a difference and it did nothing. The pot reads at 10ohms and smooth from end to end. There is ~ +385VDC or so on the input, wiper, and output of the control. I'm not quite sure where to look next.


http://i1075.photobucket.com/albums/...psupy4bl62.png

Tim 01-20-2017 01:06 PM

Did you check out the circuitry associated with the center tap?

vts1134 01-23-2017 08:15 PM

I think I've figured out the audio issue. I had a bad solder joint on the tone control. After reflowing the solder connection the problem has yet to return. I also realized the horizontal centering control does function, it's just that it doesn't have much adjustment at all. I don't know if it's functioning normally or not, but I do need a bit more shift than it's giving me. The raster is shifted too far to the left currently. I've been enjoying an episode of the Twilight Zone this evening trying to find any other issues. My list as of now:

1- Raster is off center to the left.
2- There appears to be a slight ripple present in the vertical.
3- There are three extremely faint vertical bars on the left side of the picture.
4- The picture focuses well in the center, but not at the edges.
5- The horizontal linearity isn't great.
6- The vertical deflection is collapsed on startup (although tonight it didn't happen)
7- There is a slight buzz in the audio (only audible when no audio is present)

vts1134 01-28-2017 07:57 PM

I hooked up my signal generator to the set tonight so that I could get a good video of the ripple problem. With the crosshatch pattern on the screen it makes the problem very apparent. Am I correct in thinking that I should be looking at the filter capacitors as well as the capacitors in the vertical circuitry?

https://youtu.be/qYHCJpinZZY

Findm-Keepm 01-28-2017 08:23 PM

Quote:

Originally Posted by vts1134 (Post 3177151)
I also realized the horizontal centering control does function, it's just that it doesn't have much adjustment at all.

Is there a yoke tilt screw, or are centering rings present?

Has the set been recapped yet?

vts1134 01-29-2017 04:42 PM

Well, the audio problem is back. Here is a quick video showing the problem. The area that you see in the video is around the tone control. It's the darndest thing :scratch2:. I'm thinking something has an intermittent connection to ground?

https://youtu.be/Ne6EBEhBwso

benman94 01-29-2017 05:56 PM

John,
As a cathode hollows out with use, you can get non-uniform focus from left to right. Is the CRT dying?
-Ben


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