Motorola 17K1BE Service Manual Download

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T u n e the h ig h f r e q u e n c y t r a p L -1 2 lo c a t e d on the 1st IF

c o i l f o r m a x im u m a tte n u a tio n on the c u r v e at 27 . 3 m e .

A d ju s t the 1st IF c o i l , L - l l , to p la c e a 2 6 . 6 m e m a r k e r

on the h ig h s id e o f the r e s p o n s e c u r v e 60% d o w n f r o m m a x

im u m r e s p o n s e .

S ee F ig u r e 6.

9 .

A d ju s t the 2nd IF c o i l , L - 1 5 , to p la c e a 2 2 . 7 m e m a r k e r

on the lo w s id e o f the r e s p o n s e c u r v e 6 0 d o w n f r o m m a x i

m u m r e s p o n s e .

10.

A d ju s t the 3 r d IF p la te t r a n s f o r m e r T - 2 to p r o v id e a

fla t t o p o r s y m m e t r i c a l r e s p o n s e c u r v e .

11.

R e s e t the t r a p s (s t e p s 6 and 7) and a g a in c h e c k the IF

f o r p r o p e r r e s p o n s e .

N O T E : It i s s u g g e s t e d that the b ia s b e r e m o v e d f o r a c c u r a t e

s e t tin g o f the t r a p s .

12.

W ith b ia s a p p lie d , c o n n e c t th e s w e e p b e t w e e n the g r id

(p in 2) o f the m i x e r tube V - 2 A (1 2 A T 7 ) and c h a s s i s .

13.

D is c o n n e c t the t r i m m e r , C - 1 4 , in L C c i r c u i t in the

g r id o f the m i x e r tu b e , o r s h o r t the t r i m m e r th ru a 1 0 ,0 0 0

m m f c e r a m i c d i s c typ e to c h a s s i s .

14.

B r in g b o th c o r e s o f the m ix e r t r a n s f o r m e r , T - l , s i

m u lt a n e o u s ly f r o m the o u t s id e t o w a r d s the c e n t e r .

T h e

h a l f - w a y m a r k e r s s h o u ld be 2 6 . 4 m e and 2 2 .9 m e .

N O T E : In a lig n in g the th r e e IF c o i l s , e a c h c o i l is a d ju s t e d

in d iv id u a lly , but w h en a d ju s tin g the p r i m a r y and s e c o n d a r y
o f the m i x e r t r a n s f o r m e r , the a d ju s t m e n ts sh o u ld b e m a d e
s im u lt a n e o u s ly .

T h e im p o r ta n t p o in t to k e e p in m in d is to

o b ta in a fla t r e s p o n s e c u r v e w ith a s m u c h g a in a s p o s s i b l e .
T h e s i d e s o f the c u r v e sh o u ld b e s t r a ig h t and as s t e e p as

p o s s i b l e .

S im u lta n e o u s a d ju s t in g o f the p r i m a r y and s e c

o n d a r y is the e a s i e s t w a y to o b ta in th is r e s u lt .

T h e t r a n s

f o r m e r b y i t s e l f i s , in e f f e c t , tu n ed f o r the s a m e p a s s band

as the t h r e e s t a g g e r e d c i r c u i t s .

S ee F ig u r e 7.

T h e o n ly

d i f f e r e n c e in the o v e r a l l w a v e f o r m sh o u ld b e that the s id e s
o f the o v e r a l l w a v e a r e s t e e p e r .

C o n s ta n t u s e o f the 50%

m a r k e r s (2 2 . 9 m e and 26. 4 m e ) s h o u ld b e r e s o r t e d t o ,

s in c e it is a b s o lu t e ly n e c e s s a r y to o b ta in the p r o p e r c u r v e .

A s lig h t d ip (n o t e x c e e d in g 10% ) is p e r m i s s i b l e in the m ix e r

t r a n s f o r m e r r e s p o n s e c u r v e .

B A N D W ID T H

T h e b a n d w id th m a y b e d e t e r m in e d b y c o n n e c t in g an A M

g e n e r a t o r to the m ix e r g r id .

W ith the g e n e r a t o r f r e q u e n c y

at 24 . 6 m e , a d ju s t the output f o r 1 v o lt r e a d in g on a V T V M
c o n n e c t e d to p in 4 o f t e s t s o c k e t and c h a s s i s .

D o u b le the

ou tp u t o f the g e n e r a t o r .

N ow b y tu n in g e it h e r s id e o f 24 . 6

m e and n o tin g the f r e q u e n c i e s at w h ic h the V T V M a g a in

r e a d s 1 v o lt , the 6 db b a n d w id th p o in ts a r e in d ic a t e d . T h e s e
p o in t s s h o u ld b e 2 2 .9 m e and 26. 4 m e .

B y w a tc h in g the

m e t e r w h ile tu n in g s lo w ly th ru the ba n d an y s e r i o u s p e a k s

o r h o l e s in the r e s p o n s e c a n a l s o b e d e t e c t e d .

R E G E N E R A T IO N C H E C K

A f t e r the a b o v e IF and m ix e r t r a n s f o r m e r a lig n m e n t h a s

b e e n m a d e , a c h e c k f o r r e g e n e r a t io n in the IF a m p lif ie r

s t r ip sh o u ld b e m a d e . T h is is d o n e b y r e m o v in g the b a t t e r y

b ia s and o b s e r v i n g the output r e s p o n s e c u r v e on the o s c i l l o

s c o p e , as ta k en b e t w e e n the p ic t u r e tu be c a t h o d e and c h a s
s i s .

T h e ba n d w id th m a y c h a n g e w ith the b ia s r e m o v e d but

s h o u ld n ot c h a n g e m o r e than 0. 2 m e .

S et the c o n t r a s t c o n

t r o l to m a x im u m g a in .

D e c r e a s e the inp ut u n til the output

s ig n a l s h o w s a m a r k e d d e c r e a s e . A n y r e g e n e r a t io n p r e s e n t

w ill b e in d ic a t e d b y s h a r p p e a k s on the o v e r a l l r e s p o n s e

c u r v e .

T h e o s c i l l a t o r s h o u ld b e s t o p p e d ,

a s d e s c r i b e d

a b o v e , d u r in g t h is p r o c e d u r e .

C A U T IO N : D o n ot in j e c t t o o m u c h m a r k e r s ig n a l.

M IX E R L C A D J U S T M E N T

R e c o n n e c t b ia s r e m o v e d f o r r e g e n e r a t io n c h e c k .

R e

p la c e t r i m m e r C -1 4 in L C c i r c u i t o f m i x e r g r id o r r e m o v e
10, 00 0 m m f c e r a m i c b e t w e e n t r i m m e r and c h a s s i s .

A d ju s t

the t r i m m e r s o it is tu n ed to the c e n t e r o f the m ix e r r e

s p o n s e c u r v e .

T h is is in d ic a t e d b y o b s e r v i n g the e f f e c t o f

the L C c i r c u i t on the m i x e r r e s p o n s e .

I n c r e a s in g the c a

p a c it y o f the t r i m m e r and b r in g in g the L C c i r c u i t f r o m

a b o v e the IF r a n g e in to the IF r a n g e , it w i l l be n o te d that

the m ix e r c u r v e w i l l p u ll d ow n on the h ig h s i d e , s t r a ig h t e n

out  a s  the  L C   c i r c u i t   a p p r o a c h e s   the  m id d le   o f  the  r a n g e ,
and  p u ll  d ow n   on   the  lo w   s id e   a s  the  L C   c i r c u i t   a p p r o a c h e s
the  lo w   end  o f  IF   r a n g e .

T h e p r o p e r tu n in g p o in t is that

p o in t at w h ic h the m i x e r c u r v e s t r a ig h t e n s ou t.

In e f f e c t ,

the L C c i r c u i t is s i m i l a r to a j a c k c o i l w h en it is w ith in the

IF r a n g e .

C A U T IO N : T u n in g the L C c i r c u i t v e r y lo w w il c a u s e

o s c i l l a t i o n .

IF S E N S IT IV IT Y M E A S U R E M E N T S

IF S ta g e s O n ly

R e m o v e the b a t t e r y b ia s f r o m 1st IF tu b e g r id .

C o n n e c t an A M s ig n a l g e n e r a t o r , s e t at 24 . 6 m e , th ru

a b lo c k in g c a p a c i t o r o f 5000 m m f, b e t w e e n c h a s s i s and the
g r .d (p in 1) o f the 1st IF tu be V - 3 .

C o n n e c t an e l e c t r o n i c v o l t m e t e r a c r o s s the v id e o d e t e c

t o r lo a d r e s i s t o r R - 2 8 (5 6 0 0 ).

B o th le a d s f r o m the m e t e r

sh o u ld be d e c o u p le d w ith 100K o h m r e s i s t o r s .

4 .

5iet the c o n t r a s t c o n t r o l f o r m a x im u m s e n s it iv it y .

Stop the o s c i l l a t o r tu be b y d is c o n n e c t in g r e s i s t o r R - 9

(1500) f r o m the p la te (p in 6) o f t u b e V - 2 B (1 2 A T 7 ) o r b y s u b

s titu tin g a n o th e r tu be w ith p in 6 r e m o v e d .

T h e s ig n a l r e q u i r e d to p r o d u c e 1 v o lt (n e g a t iv e ) a b o v e

c o n t a c t p o te n tia l on the m e t e r s h o u ld be l e s s than 700 m i c r o
v o l t s .

M ix e r & IF S ta g e s

T h e p r e l i m i n a r y p r e p a r a t io n s a r e the s a m e a s f o r c h e c k

in g the s e n s i t i v i t y o f the IF s t a g e s e x c e p t :

C o n n e c t the A M s ig n a l g e n e r a t o r , s e t at 24 . 6 m e , th r u

a 50 00 m m f c a p a c i t o r , b e t w e e n c h a s s i s and the g r id (p in 2)
r i the m ix e r tube V - 2 A (1 2 A T 7 ).

T h e s ig n a l r e q u i r e d to p r o d u c e 1 v o lt (n e g a t iv e ) a b o v e

c o n t a c t p o te n tia l on the m e t e r s h o u ld b e l e s s than 125 m i c r o
v o lt s .

O S C I L L A T O R , A N T E N N A A N D R F A L IG N M E N T

N O T E : T h e IF m u s t b e a lig n e d b e f o r e the R F s e c t i o n c a n
b e p r o p e r l y p h a s e d .

E q u ip m e n t R e q u ir e d :

S w e e p G e n e r a t o r : F r e q u e n c y r a n g e 4 0 - 2 2 0 m e ; 10 m e s w e e p

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Summary of Contents for 17K1BE

Page 1: ...V l l 6 V 6 G T A u dio Output V l 2 6SN7GT 1st 2nd C lip p e rs V l 3 12AU7 or 6SN7GT V e r tic a l Sw eep G en era tor V 14 6W 6GT or 6AS 5 V e r tic a l Sw eep Output V 15 6A L5 or 6H6 P h ase D e te cto r V 1 6 6SN7GT H orizon ta l O s c illa to r V 17 6BQ 6G T H orizon ta l Output High V olta ge G en era tor V 1 8 6W 4GT D am ping D iode V 1 9 1B3GT High V olta ge R e c tifie r V 2 0 17BP4 or...

Page 2: ... the lo ca tio n of the r e c e iv e r s N orm a lly the stren gth of the sign a ls w ill v a ry throughout the ro o m in w h ich the r e c e iv e r is loca te d F o r this re a so n b etter p ictu re s w ill be obtained if the r e c e iv e r is tried in all p o ssib le loca tion s in the view in g ro o m and is then p laced w h ere the c le a r e s t p ictu res a re re ce iv e d fr o m a ll stati...

Page 3: ...ddle of its range an dnote the width of the blanking p u lse T h e blanking pulse ap p ea rs as a g ra y b a r at the righ t edge of the p ictu re 3 R em ov e sh ort fr o m H O R IZ O N T A L O S C IL L A T O R c o il 4 A d ju st H O R IZ O N TA L O S C IL L A T O R c o il until the sam e am ount o f blanking pulse can be seen as w as noted in step 2 V E R T IC A L HOLD AD JU STM EN T A d ju st th...

Page 4: ...ube when the su pport b ra ck e t p osition in g adjustm en t s c r e w s a re tigh ten ed A ls o the yoke m ay be fo r c e d out of p o sitio n The opening in the yoke should be c o n ce n tric with the n eck of the tube FOCUS C O IL The fo cu s c o il should be p osition ed so that it is sp a ced l 4 fr o m the d e fle ctio n yoke when p a r a lle l with the yok e The opening in the fo cu s c o ...

Page 5: ... s y m m e try of the cu rv e m ay be ch eck ed by tuning the g e n e r ator 2 5 kc fr o m 4 5 m e and noting the volta ge p rod u ced r e v e rs in g the m eter con n ection s as n e c e s s a r y F o r p rop er ba lan ce of the ra tio d e te cto r sy ste m the volta ge in each d i re ctio n should be a p p rox im a tely equ al If not ch e ck the tuning of L 2 0 and the p rim a ry s e co n d a ry...

Page 6: ...o o s e ly cou p le the output of an a ccu ra te ly ca lib ra ted AM signal gen era tor to the IF strip At all tim e s keep the m a rk er output low enough to p reven t the m a rk er fr o m d is tortin g the re sp o n se cu rv e A D o not red u ce the o s c illo s c o p e gain and in c r e a s e sign al input s o that the top of the cu rv e is fla tten ed due to lim it ing in the v id e o o r sco ...

Page 7: ...e by rem ov in g the ba ttery bias and o b se rv in g the output re sp o n se cu rv e on the o s c illo sco p e as taken betw een the p ictu re tube cathode and c h a s s is The bandwidth m ay change with the bia s rem ov ed but should not change m o re than 0 2 m e Set the co n tra st c o n tro l to m axim u m gain D e cre a se the input until the output sign a l show s a m ark ed d e cr e a s e ...

Page 8: ...u sted it m ay be n e c e s s a r y to re a d ju st R F t r im m e r C 6 and r e ch e c k the high ch a n n els 10 M ove bandsw itch to chan nel 6 11 With ce n te r fre q u e n cy o f sw eep g e n e ra to r at the cen ter fre q u e n cy of chan nel 6 85 m e in trod u ce m a rk e rs c o r r e s ponding to sound and p ictu re c a r r ie r s and co m p a re with cu rv e of F igu re 9 N O TE A con ven...

Page 9: ...y spreadin g tu rn s T h is w ill a lso tend to m ove channel 9 sound m a rk e r out of the trap dip but this can be co m p e n sated fo r by the fine tuning trim m e r A gain do not adju st the c o il any m o re than is n e c e s s a r y to brin g the channel in qu estion b a ck w ithin the 30 d e g ree r e qu irem en t 17 T ilrn sw eep g e n e ra to r and station s e le c to r sw itch to channel...

Page 10: ... izon ta l phase d e te cto r V 15 No com pon en t changes are r e qu ired with this substitution 9 The dam ping r e s is to r a c r o s s o s c illa to r c o il L 4 E w as changed fr o m 2200 ohm s to 3900 ohm s to sta b ilize the o s c i l la tor on the low chan nels 10 In som e se ts 6AG5 tubes are substituted fo r 6AU6 tubes in the fir s t and secon d IF a m p lifier sta g es L ll the fir s t ...

Page 11: ...00V 35 8R490263 Molded paper 1 mf 600V 35 21K700883 Ceramic tubular 180 mmf 3000V 50 8R9874 Paper 1 mf 600V 35 21K790574 Ceramic tubular 60 mmf 1500V in deflection yoke 35 8R9874 Paper 1 mf 600V 35 i 23B700613 Electrolytic 3 section 80 mf 400V 20 mf 300V 10 mf 300V 2 55 C 26 21A470789 Ceramic disc 5000 mmf 450V 30 C 23B700614 C 27 21K77375 Ceramic tubular 220 mmf 500V 20 C 28 21K470329 Molded comp...

Page 12: ...R 36 12 000 not replaceable core mtg nut 80 part of L 19 L 21 24K701651 Compensating coil green dot R 37 6R5671 4700 10 2W 25 wound on R 99 50 R 38 6R3933 220 20 1 2W doz 1 20 L 22 24B700548 Focus coil 10 20 R 39 6R2004 8200 10 1 2W doz 1 20 L 23 24K790059 Horizontal oscillator less R 40 6R5660 180 10 1 2W doz 1 20 core clip 95 R 41 6R6012 33 000 20 1 2W doz 1 20 or 24B790055 Horizontal oscillator...

Page 13: ... 3 6AU6 or 6AG5 1st IF Amplifier V 4 6AU6 or 6AG5 2nd IF Amplifier V 5 6AG5 3rd IF Amplifier V 6 6AL5 or 1N60 Video Detector V 7 6AH6 or 6CB6 Video Amplifier Ref Part List No Number Description Price V 8 6AU6 or 6AG5 Audio Driver Limiter V 9 6AL5 Ratio Detector V 10 6J5 GT Audio Amplifier V ll 6V6 GT Audio Output V 12 6SN7GT 1st 2nd Clipper V 13 12AU7 or 6SN7GT Vertical Sweep Generator V 14 6W6 or...

Page 14: ...le to miniature socket Plate chassis cover removable plate on chassis side 64A90034 Plate electrolytic mtg for two electrolytics 05 64A700690 Plate electrolytic mtg for three electrolytics doz 35 64K700748 Plate socket cover covers unused hole when two electrolytics used doz 30 64A700745 Plate transformer cover for 25C700161 25K700882 transformers only 10 1X700523 Plate tube mtg with socket mtg br...

Page 15: ...10 1 00 50 50 50 50 50 15 Part Number Description List Price 4A77577 Washer insulating L 27 mtg doz 15 39A702285 Wiper grounding on tuner switch assembly 05 Insulating Compounds 11M490423 Coating hi voltage insulating red brn on hi volt rect socket 11M490387 Wax biwax on hi voltage trans MODEL 17K1E CABINET PARTS 1X702641 Back Cover complete with picture tube rear cover centering ad justment cover...

Page 16: ...mtg per c 50 35K792499 Pad cushion window mtg doz 30 55K700796 Pull door pol brs 1 60 5S7703 Rivet 122 x 7 32 stl pol nkl picture tube rear cover mtg per c 50 5S6846 Rivet 145 x 5 32 stl pol nkl hi volt insulator mtg doz 15 3S2226 Screw machine 1 4 20 x 1 1 4 plain hex head cad pi chassis mtg doz 50 3S7374 Screw machine 8 32 x 5 16 plain hex head cad pi bezel mtg per c 50 3S7536 Screw sheet metal ...

Page 17: ...Scanned by mbear2k Jan 2012 ...

Page 18: ...TELEVISION CHASSIS TS 172 Date 24 November 1950 Diag No 63E702110 0 LSI Scanned by mbear2k Jan 2012 ...

Page 19: ... SIGNAL OF 45 VOLTS PEAK TO PEAK LEVEL AT PLATE OF VIDEO AMPLIFIER ALL OTHER CONTROLS IN OPERATING POSITION DUMONT 241 SCOPE a LOW CAR PROBE USED RESISTORS INDICATED IN OHMS K IOOO ONE THOUSAND OHMS CAPACITORS INDICATED IN MICROMICROFARADS UNLESS OTHERWISE SPECIFIED INDUCTANCES INDICATED IN MICROHENRIES UNLESS OTHERWISE SPECIFIED cautio n DO NOT ATTEMPT VOLTAGE READINGS ON HIGH VOLTAGE RECTIFIER O...

Page 20: ...G WITH R64 VI4 I J 6W6GT VERT SWEEP OUTPUT SEE ALSO DETAIL O VERT LIN JL C69C OR C68B I50K REP7 YOKE HORIZ 38 OHMS 2700 IOOK IQOV VI7 6BQ6GT IORIZ OUTPUT a H V GEN VI9 L24C IB3GT H V RECT jI4 K V T6 D C RESISTANCES TERM RES 1 TO 2 1 2 OHMS 2 TO 3 10 OHMS 3 TO 4 9 OHMS 4 TO 5 70 OHMS V20 17BP4 OR 17AP4 PICTURE TUBE PI AG N0 63E70g IQ 0 Scanned by mbear2k Jan 2012 ...

Page 21: ...AL5 1N60 XT VIDEO DET IN PLACE SOME SE TO GRN _ U l T 9 f h 1 T Z 5j N x L USED OF V6 IN TS i LI6 1 Y 7 C37 _ _ NOT USED __ 1 V RFC G C R 1 C R 1 REPLACES R46 C 5 4 a R 4 7 IN SOME SETS Scanned by mbear2k Jan 2012 ...

Page 22: ...V7 6CB6 VIDEO AMR IN SOME SE TS VERT VI3 6SN7 VERT SWEEP GEN IN SOME S E T S Scanned by mbear2k Jan 2012 ...

Page 23: ...ILS LI I a LI5 CHANGE WHEN 6AG5 TUBES ARE USED F T V3 6AG5 I ST IF AMP IN SOME SETS V4 6AG5 2ND IF AMR F VI5 6H6 PHASE DET IN SOME SETS a R33 r CR3 CR3 REPLACES C59 R58 R59 C60 R60 ft C6I IN SOME SETS Scanned by mbear2k Jan 2012 ...

Page 24: ...the H orizon ta l H old co n tro l to about the m idd le of its ran ge and note the width of the blanking p u lse T h e blanking pulse ap p ea rs as a gray bar at the righ t edge of the p ictu re 3 R em ov e sh ort fr o m H orizon ta l O s c illa to r c o il 4 A d ju st H orizon ta l O s c illa to r c o il until the sam e am ount of blanking p u lse can be seen as w as noted in Step 2 REPLACEMENT ...

Page 25: ...NOTE STATION SELECTOR SWITCH SI SHOWN IN CHANNEL NO 2 POSITION 0 IRON TUNING CORES t BRASS TUNING CORES Tl CONNECTIONS 1 0 L 18 a L CONNECTK ______ 12 AT 7 ______ P C 2 5V I MIXER 105V g _ _ 1 I 1 i CH L i L r i i t SEE ALSO DETAIL E V3 6AU6 1ST IF AMP Scanned by mbear2k Jan 2012 ...

Page 26: ...Motorola TELEVISION CHASSIS TS 172A Diag No 63E702144 0 L S I Scanned by mbear2k Jan 2012 ...

Page 27: ... FOR SIGNAL OF 45 VOLTS PEAK TO PEAK LEVEL AT PLATE OF VIDEO AMPLIFIER ALL OTHER CONTROLS IN OPERATING POSITION DUMONT 241 SCOPE 8 LOW CAP PROBE USED v RESISTORS INDICATED IN OHMS K IOOO ONE THOUSAND OHMS CAPACITORS INDICATED IN MICROMICROFARADS UNLESS OTHERWISE SPECIFIED INDUCTANCES INDICATED IN MICROHENRIES UNLESS OTHERWISE SPECIFIED c a u t i o n DO NOT ATTEMPT VOLTAGE READINGS ON HIGH VOLTAGE ...

Page 28: ...Dl AG MO 63 E 702144 0 Scanned by mbear2k Jan 2012 ...

Page 29: ...T V 6AL5 VIDEO DET TO GRN XTAL USED IN PLACE OF V6 IN SOME SETS J l_ E l T2 5 1 IN 1 1 i LI6 NOT USED _ 6 C37 RFC C VERT SWEEP GEN IN SOME SETS Scanned by mbear2k Jan 2012 ...

Page 30: ...V3 6AG5 I ST IF AMP IN SOME SETS V4 6AG5 2 ND IF AMP Tl MIXER IF 1500 C24 n o t e t i l i i a l i 5 c h a n g e WHEN 6AG5 TUBES ARE USED VIS 6H6 PHASE DET IN SOME SETS Scanned by mbear2k Jan 2012 ...

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