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Hi Karesz,
I solved the problem. Btw, the first thing which i've checked was G2 voltage for retrace lines and it was correct. For hum, i would check bridge rectifier but found problem before on degauss coil PTC and solved it too. Thank you again for response.
Yes, there are two separate coils. One at the upper back side, one at the lower back side of the tube. Maybe this was the reason of two bars.
ps- i couldnt find a replacement PTC in the nearby electronic components store but i've replaced it with the PTC of a 14" PC monitor which was pending at...
Before starting to scoping, I wanted to start from the simplest thing which you've recommended before and found the problem on degauss circuit!! After the disconnection of the connector of degauss coil while TV is operating with parasitic lines on screen, lines disappeared instantly. To be sure...
I have a dual trace(with add-subtract modes) 20Mhz analog scope and i have two probes (1x-10x each). Maximum input rating written on the scope near BNC probe connectors is 300V peak. It also has TV-H and TV-V trigger sync modes .
If the checks that you've said does not help then lets wait for Brian's input. Is there a safe way to disable and isolate E-W correction circuit (like removal of L804, C827 and maybe R828) to check the lines disappeared or not. Maybe it could help us to identify the problematic section??
Thank you for your quick answer. After taking the measurements, could i verify startup circuit alternatively by disabling it after turning the tv on (i mean for example by mounting a temporary switch between D601 and R604 and breaking the circuit after powering the tv on) I dont think it will...
I solved the first problem. By using the Capacitance-ESR meter that i've built. i removed and measured all electrolytic caps except the ones at tuner section. Some of them, especially few caps in power supply and one cap in horizontal deflection are way out of tolerance in means of ESR (i mean...
Yes, pincushion and east-west should be the same thing if i remember right too.
I'll check the voltage of IC501 between pins 2 and 6. Horizontal drive and vertical drive has some connection between (L804, Q804-Q805 and other components shown near vertical IC on schematic.) for pincushion...
Hi Brian,
You can find the schematic on my 2nd post. I re-orineted the pages to ease tracking at 2-page side by side mode on acrobat reader.
You can watch the video below too (but you need to watch after download since dropbox applies a conversion which reduces quality and hides the lines) I...
Distortion is equal on left and right sides, but center of the screen is almost free from distortion. (first three pics are showing only upper-right part of the screen, not the whole) I've sent you links of three videos recorded at TV broadcast via pm. In these videos distortion is clearly...
Sorry, i expressed the problems a little bit unclear. I have two unrelated problems.
About the first problem (retrace lines on top of the picture):
I'll check the voltage on pin 6 and D501 soon. Image is centered vertically. If i move the centering pot, lines are moving together with image. If...
IC501 pin2 measures 28.80-28.95 V DC. I measured all other supply voltages too. These are:
190V: 191.0 V
135V: 135.1V
5V: 4.82V
8V: 8.58V
18V (also defined as 21V on some parts of the schematic): 20.28V
24V seems to be derived from FBT, and input votage (135V) of FBT is perfect...
I replaced all electrolytic capacitors in vertical deflection circuit, including C504. But unfortunately nothing changed. Retrace lines are still there. I found some weak solders and re-soldered them all on several parts of the board, including power supply, horizontal deflection, vertical...
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