Scan lines at top when flyback replaced! RCA F32650

[[email protected]]

When I replaced the flyback transformer & HOT in this set (original
faulty parts), I have a few scan lines visible at the top of the
screen. I cannot seem to get any adjustment to fix it. The flyback is
a substitute replacement from the original and I feel it may have
caused this problem. The picture is fine except for these scan lines
that are visible. Has anyone fixed or seen this problem after
replacing the original flyback with a sub? What can be done to correct
this? Supplier says original is NLA.

 

[carneyke]

Dumb answer but did you adjust the Screen control on the flyback ?

 

[[email protected]]

yes, i did. These are not retrace lines, they are scan lines.

 

[Dani]

You have to go into the EEPROM service menu to slightly adjust the
vertical height.
Be carefull doing this. Write down the values you see, so you can
adjust them as
necessary, & do one increment at a time! Adjust P05, & P06. Look below.
Hope this
helps, Dani.


http://myweb.accessus.net/~090/how2adj.html#5.4


2. Press and hold MENU
3. Press POWER
4. Press VOL+
5. P00 and V00 will be displayed
(left and right sides of screen)
6. Release MENU
7. Press VOL+ to set V00 to V76
8. Press CH+ to select and adjustment
that you want to change ( "P00" )
9. Press VOL+ and VOL- to adjust

P01 Hours Freq. P07 Red Bias
P02 Hours Phase P08 Grn Bias
P03 EWDC P09 Blue Bias
P04 EW amp P10 Red Drive
P05 Vert Cent P11 Grn Drive
P06 Vert Size P12 Blue Drive

 

[[email protected]]

Hi Dani,

Thanks, I;ve already tried the vertical size and vertical shift in the
service menu, but the picture seems to fold over after so much
adjustment. I can't adjust to totally get rid of the scan lines.
Might there be some circuit modification that could be done to solve
this problem.

I've read some posts about this flyback problem. Looks like you've run
into this one before! Did adjusting vertical size fix the problem for
you? Did you use substitute parts or originals?

Tyrone

 

[Dani]

Slight tweaking in the EEPROM has ALWAYS fixed these units after a
generic flyback.
Also, adjust the G-2 so it's not too high. Dani.

 

[[email protected]]

first off please excuse the spelling i'm an electronic tech not an
english major.

i have the exact same problem

after adjusting vert settings in the sevice menu (this fixed the scan
lines) except when the screen is black during a channel change or vid
input change which leads me to.......

i noticed another problem

when watching cnn or espn when the picture gets brighter the running
ticker on the bottom of the screen will boom out (enlarge, picture size
increeses) when the image gets darker the picture shrinks ????????????

i adjusted the screen voltage to 211 volts as shown on the sams
photofact (set 4792.pdf) that the suplier of the flyback was kind
enough to send me. this gave me to dark of a screen
and the osd menu black. turnning up the screen control till osd is good
(requires very little adjustment very touchie ) now when monitoring the
screen voltage at pin 7 of the crt the voltage varries from 206-224v
depending what is on the screen dark pic or bright pic. if camera
flashes are displayed the voltage really goes up and down.

also to let you know i replaced the H.O.T. (TL02),
tp20,tp23,tp22,dp22,dp31,rp21 (all fried by the flyback),

and all the caps except the smd's in the LV-PS with parts scavanaged
from a good CTC203 chassis witch is almost identical to the ATC113. in
the lv and hv sections. in an attemp to correct this problem.

130v source in th LV-PS stays rock solid at 129.8v.
17v source is at 16v
9v source is at 8.8v
5.2v source is at 5.2v
-11.7 source is at -11.7v
15.3v source is at 15.2v
and my 14v sorce (tp21) on print is at 16v. this is part of the
flyback supply it feeds the sence curciut TP553 and the tilt curcuit
and coil.

i think its the flyback or the crt?

I'm Frustrated!!!!

COOSIE

 

[[email protected]]

I think I'm gonna try to get another flyback for this model from a
different source. Also, I'm gonna see if I can source the original!
Anyone in Canada know of any possible places?

Thanks

Tyrone

 

[[email protected]]

The change is picture size as a function of the brightness is due to
hogh-voltage variations. WHen the picture is darker, the high voltage
goes up and accelerates the beam faster and this doeos not allow as big
a scan befire the beam hits the phosphors.

H. R. Hofmann

 

[Art]

Sad to say but all comon symptoms of the after market ASTI devices being
supplied.