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Need help Sharp 21V-K200S wont turn on

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dboy23:
I already have TV diagram (pls see attachments, power supply only). And I found out that R511 (1.5 ohms near FBT to 24V Vcc of Vertical IC) was open. After replacing this resistor, then turning on the TV, this resistor burned. I tried to remove the vertical IC and replace again the R511 resistor and check the 24V Vcc line of this IC and I measure around 30V instead of 24V (note: CRT is detached to the board when measuring). Anyone could explain why I measure 30V instead of 24V when vertical IC was removed?  Does vertical IC influenced the FBT input? And also 185V (YBN1) is only 100V.  Pls advise.

Note: 115V and 12VA on the 1st page are already ok. IC751 input and output are also ok.

nhoy_mags:
hi,replace the vertical IC..this IC is shorted.reason  why the resistor keeps blowing.don't woryy the 30 volts,its normal since there is no load(vertical ic).

dboy23:
Thanks nhoy_mags!
I will buy and replace this vertical IC.
Do you have an idea about the 100V instead of 185V on YBN1?

nhoy_mags:
check feedback IC(SE115 or 120).or check any capacitor rated .47uf.around the regulator IC.

dboy23:
after replacing the vertical IC and R511, the TV is now OK.
YBN1 voltage is now 185V when the board is connected to the CRT (if not connected, it is still 100V).

Thanks to nhoy_mags and to this site!

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