Ikegami HTM-1517R, Service Manual

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RGB OUT BOARD
1-B-22
(1) Circuit Structure
(a) Voltage amplifying Circuit
(b) Current amplifying BFS (Beam Feedback System) switch Circuit
(c) BFS (Beam Feedback System) sampling-hold Circuit
(d) Ripple Filter
(2) Adjustment Method
* When not otherwise indicated, HDTV is the standard for the input signal in the analog component of YPbPr.
* The figures are images are differ from the actual signals.
(a) VR101 [R FREQ.COMP]
VR201 [G FREQ.COMP]
VR301 [B FREQ.COMP]
Input the sweep signal to Y and flatten the difference in the levels of the encircled sections from low level
to medium level in the test points TP1 (R), TP2 (G), TP3 (B) of the CRT SOCKET BOARD.
Finally, adjust the Frequency Characteristic 1dB/-3dB up to 25 MHz.
Note: Use the 100:1 high voltage/low capacity probe.
60Hz
+1dB Standard
25MHz 30MHz
-3dB
60Hz
+1dB Standard
25MHz 30MHz
-3dB
60Hz
+1dB
Standard
25MHz 30MHz
-3dB