Thorn TX90 Stock Faults -

Ferguson	TX90	Flicking lines & partial field collapse.	DJ on field o/p transistors.
Ferguson	TX90	Field top & bottom foldover	Tr105 – used TIP120 as replacement
Ferguson	TX90	Field foldover in centre of screen	TDA4500 IC102 – pin 2 volts low
Ferguson	TX90	field collapse when heated	DL08 1N4148 o/c – 9v supply to IL01 TDA8214B low at 5v
Ferguson	TX90	Field collapse & no chan display then dead	1.6A fuse blows, loptr s/c used TIPL791A; R203 33R o/c; R200 390R o/c
Ferguson	TX90	Field collapse	R187 6k2 o/c
Ferguson	TX90	Partial Field collapse	R203 o/c
Ferguson	TX90	Feild collaspe or linearity faults	D106 u/s
Ferguson	TX90	Faint colour – lack of contrast or brightness	R231 ( 143k )
Ferguson	TX90	DISTORTED SOUND	R255
Ferguson	TX90	dist pic with hum bar	dry joints TR107
Ferguson	TX90	Dim pic Brightness & contrast have no effect	R233 o/c
Ferguson	TX90	Dead.	L120 s/c turns.
Ferguson	TX90	DEAD APART FROM STBY LED	RP71 9k1 LOW DP36 SC
Ferguson	TX90	Dead 1A fuse blows	T9064V Tr112 leaky; T107 leaky – used TIP41 started as dry joints
Ferguson	TX90	Dead 1.6A fuse blown	R4050 loptr leaky – replaced with TIPL761A and replace LOPTx

Ferguson	TX90	DEAD , FUSE BLOWN , LOP TRANSISTOR S.C.	CHECK TUNING CAP C194 5.6nf
Ferguson	TX90	Dead – when changing channels – intermittent	Drys on frame o/p transistors.
Ferguson	TX90	Dead – tripping noise.	R225 HT lines present no A1 volt or focus 10kv EHT.
Ferguson	TX90	Dead – reduced height & no sound.	R144 , TDA4500.
Ferguson	TX90	Dead – mains fuse under mains tfmr o/c	mains rect BY127 s/c
Ferguson	TX90	Dead – fuse FS102 blown.	W120 , W123 ( BY127 )
Ferguson	TX90	Dead – blowing line transistor.	Tr107 , 108 s/c , LOPTX
Ferguson	TX90	Dead – blowing FS1p 1.6amp intermittently.	Check holder is ok & change all 4 recy’s to BYD33G type.
Ferguson	TX90	Dead – blowing FS101 1A Fuse.	D123 ( BY127 ) s/c.
Ferguson	TX90	Dead – 12v rail ok but no 150v rail.	T103 primary o/c.
Ferguson	TX90	Crackle on sound.	IC105 12v reg
Ferguson	TX90	CRACKLE ON SOUND WITH VOL AT MIN : Ripple on Pic	IC105 12v REG
Ferguson	TX90	Crackle on sound if volume is increased.	C166 ( 100nf ) o/c.
Ferguson	TX90	Contrast – weak – low video – no sound.	IC804.
Ferguson	TX90	Contrast – low & heavy line striations.	C195 ( 0.1uf ) o/c.

Ferguson	TX90	Computer mod for boarder size.	Fit MA15 width reducer kit ( SP5611 ) to TV.
Ferguson	TX90	Computer CPC464 – missing video.	Re-setting amplitude controls.
Ferguson	TX90	Colour – very faint.	R231 ( 143k ) o/c.
Ferguson	TX90	Colour – drop out when volume is increased.	C166 not fitted ( 0 1uf ) ( 100nf ) or o/c model 14C2.
Ferguson	TX90	Channels sequencing – no 12v rail.
Ferguson	TX90	Channels – continuous ch stepping – when hot.	Fit diode D913 ( PH425 ) in place of link 925 +to C906.
Ferguson	TX90	Channels – changing at switch on fom wall.	TR904/3/2 o/c.
Ferguson	TX90	Channel – change will not work from set.	C908n leaky.
Ferguson	TX90	CH1 lights – no sound or picture.	TR902.
Ferguson	TX90	Brightness reduced & no colour.	R171 ( 120k ) high replace with 270k.
Ferguson	TX90	BLANK SCREEN , NO ON SCREEN GRAPHICS	LEAKAGE IN PCB MATERIAL AROUND CLOCK AND AND DATA LINES BETWEEN MICRO AND OTHER ICs , CLEAN BOARD OFF WITH SOLVENT
Ferguson	TX90	Blank raster with no sound	TDA4503
Ferguson	TX90	Bang – tripping then shutdown.	TR916 s/c causing C915 , D908 , TR917 , TR901 to fail.
Ferguson	TX90	Bands move upward and line tearing	C189 22µ 50v in boost reg cct
Ferguson	TX90	Band moving up the screen.	C189 ( 22uf , 50v )