#16
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I would appreciate any help i could get.
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#17
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What is the set currently doing when you try and run it?
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#18
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Tuner lights no picture no sound
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#19
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I recall an issue with solder joints on these sets. If you have HV, but no sound, that points to a "power supply" voltage common to both audio and video.
The key thing to remember is that not all power supply voltages come from a resistor (or voltage ladder) off the main power supply from the power transformer. Many of these lower voltages are derived from a winding tap on the flyback, that feed a rectifier diode and finally a smaller value electrolytic cap. See if you have DC on the cathodes of any rectifier diodes fed from the flyback. Often, there is a low value or "fuse" resistor in series there. I do not have the schematic on a set this new, but I could point it right out if someone could post it. |
#20
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Have you resoldered the pins on the modules yet? That used to be the first thing I did to these sets years ago. I sure hope I'm thinking of the right chassis about now...
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Audiokarma |
#21
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Soldered all the connections on the chassis till i got to the left under the picture tube. Did not have time to get to the video or audio boards on the left or the tuner. The picture came on in black and white, still no sound. Picture stretches a little to the right. Color sometimes appears when scene changes. Do i need to solder the rest or does it have a defective video or audio board?
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#22
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Finished resolder, now when it comes on picture is red, no sound and the suction cup wire is arcing off bad at top of tube. If it is not the tripler then what would cause this?
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#23
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Have you cleaned the bell of the CRT? Have you cleaned the suction cup?
You've probably bridged a solder connection. Check your work. Did you solder the modules themselves, too? Have you got a good magnafying (?) glass and a bright light source? Last edited by holmesuser01; 05-20-2012 at 04:41 PM. |
#24
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I am a little confused. Last week i resoldered the half of the chassis that has the flyback and it came on. Displayed a black and white picture with no sound. This week i resoldered all the modules on the sound and color half of the chassis and the flyback starts arcing. Still no color except for red and no sound. Why the arcing when i did not work on the flyback. I did solder the connection pins on the color and sound side of the main board. I double checked my work, no cross solder. Could the flyback or tripler be getting too much voltage?
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#25
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How about the ground stakes that hold the circuit board to the chassis frame?
I wish I could see an image of what you are doing. Whats the flyback arcing to? |
Audiokarma |
#26
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I resoldered the ground stakes. The arcing is coming out from under the suction cup. I will try to post pictures.
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#27
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Definitely clean the bell of the CRT around the HV connection. Be sure to discharge the CRT before you do anything having to do with this connection. Also, If you can find some silicone grease, clean the suction cup and put just a dab of the grease around the edge that touches the tube.
Is the ground connection from the CRT still connected to the chassis properly? This can cause wild problems, too. |
#28
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Like Holmesuser01 said, clean the bell and cup first. Check your HV. If it's too high, it can arc even if it's clean.
__________________
"It's a mad mad mad mad world" !! http://www.youtube.com/user/mwstaton64?feature=mhee |
#29
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Flyback
Pictures of my Magnavox. Blue arc can be seen at top on right in picture three. Picture is faded.
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#30
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Flyback
Pictures
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Audiokarma |
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