Technical Specs

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(2) C344 is the Cs capacitor, and Q324 controls C345, Q326 controls C347, Q325 controls C346, Q327
controls C348. The U701 pin 1, 2, 3, 4 controls the Q324, Q326, Q325 and Q327 respectively. So
different frequency has different combination to meet the requirement.
Cs Table By Frequency
CS1 CS2 CS3 CS4
fH < 30K 0 0 0 0
30K < fH < 34K 0 0 0 0
34K < fH < 37K 0 0 1 0
37K < fH < 46K 0 1 1 0
46K < fH < 53K 1 0 0 1
53K < fH < 63K 1 1 0 1
63K < fH < 68K 0 0 1 1
68K < fH < 75K 1 0 1 1
75K < fH < 85K 0 1 1 1
85K < fH < 86.5K 1 1 1 1
86.5K < fH 0 0 0 0
6. FBT Secondary & Dynamic Focus
(a) Focus and screen voltage are come from FBT bleeder.
(b) G1 bias is controlled through R399, R30F, VR304, R30B and Q323.
(c) Q309 is controlled by MCU pin 31 Mute2, and it will blank the picture during mode change.
(d) Q401 is the blanking buffer to G1 to blank the retrace line of picture.
(e) Q339, Q340, D302,ZD301,D326,R322 and R318 are the x-ray protection circuit. Once the HV rises
abnormally, U301 win shut down itself, all the horizontal deflection is stopped by then.
(f) Dynamic Focus:
(1) H-Focus: U301 pin 10 outputs a parabolic waveform and through Q302 into Q338 to get a reverse
amplified waveform. This waveform is through the SEPP Q303 and Q304, as a current gain then
input into T303.
(2) V-Focus: U401 pin 5 output waveform through R329, C322, R32G and C324 to get a parabolic
waveform. This waveform is amplified by Q305 and input into T303.
(3) H-Focus and V-Focus are into T303 to get a combined waveform that will input to FBT.