Conversion of Studio Lighting for Color Television

P . W . W Y G Α Ν Τ

Stat ion W B A P - T V i n Fort W o r t h h a s c o n v e r t e d its s t u d i o l i g h t i n g to p e r m i t color t e l ecas t ing . T h e p r o b l e m s e n c o u n t e r e d a n d t h e i r so lut ions

are o u t l i n e d .

TH E C O N V E R S I O N from b l a c k - a n d - w h i t e to co lor te levis ion i n t r o d u c e s n u m e r o u s l i gh t ing p r o b l e m s . A l ­t h o u g h some of t h e p r o b l e m s a r e c o m m o n to all s ta t ions ,

o t h e r s wil l b e different a t e a c h i n d i v i d u a l s t a t ion ; for ex­a m p l e , t h e p r o b l e m s of i n t e g r a t i n g a n e w l i gh t i ng sys tem w i t h t h e o ld ins ta l la t ion , t h e t y p e of p r o g r a m m i n g a n ­t i c i p a t e d , t h e pe r sonne l ava i l ab l e , a n d t h e e v e r - v a r y i n g b u d g e t . T h i s a r t i c le descr ibes t h e p a r t i c u l a r needs of S t a ­t i on W B A P - T V , F o r t W o r t h , T e x . , a n d h o w these n e e d s w e r e m e t .

ORIGINAL E Q U I P M E N T

T H E STUDIO t o b e c o n v e r t e d w a s c o n s t r u c t e d in t h e s u m ­m e r of 1948 (Fig . 1 ) . T h e s tud io is 82 feet long , 45 feet w i d e , a n d 28 feet h i g h . A p i p e gr id is m o u n t e d 20 feet a b o v e t h e floor. T h i s gr id is c o n s t r u c t e d of l V ^ i n c h g a l v a n i z e d p i p e a r r a n g e d in 7-foot s q u a r e s s u s p e n d e d f rom t h e cei l ing. A 3-foot c a t w a l k , 14 feet a b o v e t h e floor, r u n s a r o u n d t h e t w o sides a n d o n e e n d of t h e s tud io .

T h e l igh t ing f ixtures a n d c o n t r o l e q u i p m e n t in u se j u s t b e f o r e t h e convers ion t o co lor w e r e essential ly t hose p u r ­c h a s e d a n d ins ta l led in F ig . 2 . E a c h f i x t u r e c o n t a i n e d 12 l a m p s of w h i c h 6 w e r e t y p e PAR-38 floods a n d 6 w e r e t y p e 6R-40 floods. S e p a r a t e c i rcu i t s w e r e used t o supp ly p o w e r t o t h e t w o types of flood l a m p s . T h e PAR l a m p s w e r e used for m o d e l i n g w h e r e a s t h e R-40 l a m p s w e r e used for fill l igh t . E a c h f ix ture was des igned to p e r m i t to a d j u s t m e n t in a z i m u t h a n d e l eva t ion . A 360-d e g r e e t u r n p lus t i l t a d j u s t m e n t s w e r e m a d e b y m e a n s of co rds r u n n i n g to a c e n t r a l l oca t ion . S i m i l a r t u r n a n d t i l t a d j u s t m e n t s w e r e p r o v i d e d t for 15 fluorescent f ixtures . T h e fluor- 1 escen t f ixtures e a c h c o n t a i n e d six 64- I i n c h s l iml ine t u b e s . Back l igh t w a s 1 p r o v i d e d b y F resne l " s p o t s " w h i c h I w e r e m o u n t e d o n t h e c a t w a l k ra i l . {J

Full text of paper 56-76 presented at the AIEE ^ Winter General Meeting, New York, Ν. Y., January j j 30-February 3, 1956, and recommended for publica- 11 tion by the AIEE Committee on Television and Aural 8j Broadcasting Systems.

P. W. Wygant is with Station WBAP-TV, Fort Worth, Tex.

T h e n 2-k i lowat t spots a n d t en 7 5 0 - w a t t spots w e r e in use . T h e to t a l w a t t a g e f rom all f ixtures a m o u n t e d to 62

k i lowat t s , o r a p p r o x i m a t e l y 18.5 w a t t s p e r s q u a r e foot. I n 1948 a n d 1949 it w a s t h e p r a c t i c e t o p r o v i d e 200 foot c a n d l e s for u s e w i t h t h e 5655 i m a g e o r t h i c o n tubes . W i t h t h e f ixtures t h e n ava i l ab l e , i t w a s n o t possible t o p r o v i d e 200 foot c a n d l e s a r o u n d t h e four wal ls of t h e s tud io . H o w ­ever , b y m e a n s of t h e t u r n a n d til t con t ro l s , t h e l ight cou ld b e c o n c e n t r a t e d o n a n y t w o or t h r e e a r e a s in use a t a n y o n e t i m e . L a t e r , w i t h t h e d e v e l o p m e n t of t h e m o r e sensi t ive 5820 i m a g e o r t h i c o n p i c k u p t u b e , on ly 100 foot c a n d l e s of s t u d i o l i g h t i n g w a s r e q u i r e d . A 100 foo t -cand le i l l u m ­i n a t i o n c o u l d b e p r o v i d e d u n i f o r m l y for a n y a r e a in t h e s tud io w i t h o u t t u r n i n g f ixtures .

ORIGINAL LIGHTING SWITCHBOARD

T H E SWITCHBOARD w a s de s igned to h a n d l e 140 s e p a r a t e c i rcui t s , w i t h 140 s i l en t - type m e r c u r y swi tches b e i n g used t o c o n t r o l r e m o t e l y a s imi la r n u m b e r of r e l ay c o n t a c t o r s . E a c h swi tch w a s r a t e d a t 10 a m p e r e s , a n d t h e l o a d c o n t a c ­tors h a n d l e d t h e l o a d c u r r e n t of 20 a m p e r e s . O n e r e l a y l oad c o n t a c t o r w a s used for e a c h l oad r ecep t ac l e . E a c h l oad c i rcu i t w a s p r o v i d e d w i t h a 2 0 - a m p e r e b r e a k e r . T h e l o a d c o n t a c t o r s w e r e fed f rom t w o 2 0 0 - a m p e r e m a i n b r e a k e r s in t h e p o w e r feed.

Fig. 1. W B A P - T V studio showing original lighting equipment

2 7 6 Wygant—Convernon of Studio Lighting ELECTRICAL ENGINEERING

W i t h t h e a d v e n t of t h e t y p e 5820 i m a g e o r t h i c o n t u b e t h e r e w a s a lessening of t h e in f ra red p r o b l e m n o t i c e a b l e w i t h t h e ea r l i e r t ypes of p i c k u p t u b e s . A t this s tage , a d i m m e r b o a r d of 12-k i lowat t c a p a c i t y w a s c o n s t r u c t e d a n d p l a c e d i n t o o p e r a t i o n . I t w a s u sed o n l y b y those des i r ing ve ry spec ia l l i gh t ing effects, s ince its o p e r a t i o n necess i t a ted t h e r u n n i n g of ex tens ion cab les a l o n g t h e g r id f rom t h e d i m m e r t o t h e f ix ture . T h e r e f o r e , a g r e a t d e a l of l a d d e r w o r k w a s r e q u i r e d for d i m m e r effects. I n fact , t h e m a i n ob jec t ion to t h e c o n t r o l s w i t c h b o a r d b y t h e o p e r a t i n g p e r ­sonne l was its pos i t ion o n t h e c a t w a l k 14 feet a b o v e t h e s tud io floor. T h e l o a d c o n t a c t o r s w e r e subjec t to s t icking, t h u s l eav ing t h e c i r cu i t c o n t i n u a l l y h o t u n t i l s o m e o n e filed o r r e p l a c e d t h e c o n t a c t po in t s . F ig . 3 shows t h e l oca t i on of t h e o r ig ina l s w i t c h b o a r d on t h e c a t w a l k .

AIR CONDITIONING

As IT is W E L L K N O W N , t h e s u m m e r s of T e x a s a r e n o t n o t e d for b e i n g m i l d . O n e of t h e first p r o b l e m s a t W B A P - T V was t h e d isposa l of t h e a d d i t i o n a l h e a t t o b e g e n e r a t e d b y t h e inc reased l igh t ing l oad . A h e a t e x c h a n g e r w a s bu i l t on t h e roof of a n ad jo in ing b u i l d i n g w i t h c o n n e c t i n g d u c t s feed­i n g in to o n e e n d of t h e s tud io . T w o 100- ton c o m p r e s s o r un i t s w e r e a l r e a d y in use . O n e 60 - ton c o m p r e s s o r u n i t was a d d e d to t h e exis t ing c h i l l e d - w a t e r l ines w h i c h w e r e e x t e n d e d t o t h e n e w h e a t e x h a u s t . A d d i t i o n a l d u c t s w e r e a d d e d a b o v e t h e g r id in t h e s t ud io . T h e n e w s t u d i o a i r -c o n d i t i o n i n g c a p a c i t y w a s a l m o s t d o u b l e d ove r t h a t of t h e exis t ing ins ta l l a t ion .

PRIMARY POWER

T H E SUBSTATION i n use in 1954 b e l o n g e d to t h e T e x a s Elec t r ic Se rv ice C o m p a n y a n d h a d a 450-kva c a p a c i t y . T h e t h r e e t r ans fo rmers in use w e r e p u r c h a s e d f rom t h a t c o m p a n y . T h r e e s imi la r 150-kva t r ans fo rmer s w e r e a d d e d

to t h e t r a n s f o r m e r b a n k t o g ive a t o t a l of 900-kva ins ta l led c a p a c i t y . T h e t o t a l l o a d w a s n o t e x p e c t e d t o b e d o u b l e d , b u t i t w a s felt t h a t t h e r e se rve p o w e r c a p a c i t y w o u l d suffice for poss ible fu tu re n e e d s . W h e n t h e n e w t rans formers w e r e ins ta l led , t h e c o m p l e t e subs t a t i on w a s p u r c h a s e d f rom T e x a s E lec t r i c . I t a p p e a r e d t o b e a n e c o n o m i c a l m o v e to p u r c h a s e t h e s u b s t a t i o n s ince t h e sav ing in p o w e r costs w o u l d p a y for t h e t r ans fo rmer s w i t h i n a p p r o x i m a t e l y six yea r s .

I n t h e b a s e m e n t p o w e r vau l t , a n e w 150-kva t r ans fo rmer w a s a d d e d to t h e s e c o n d a r y b u s . F o r t u n a t e l y , t h e r e w a s s p a c e to fit t h e n e w t r a n s f o r m e r in t h e s a m e r o o m w i t h t w o s imi la r 150-kva t r ans fo rmer s a l r e a d y in use . T h e n e w t r a n s f o r m e r feeds 1 2 0 - 2 0 8 vol t , 3 -phase , 4 -wi re service t o a 4 0 0 - a m p e r e m a i n b r e a k e r . T h e second t r ans fo rmer feeds t w o 2 0 0 - a m p e r e b r e a k e r s , o n e of w h i c h is t h e m a i n for l i gh t ing i n a n o t h e r te levis ion s t ud io .

T h e u t i l i ty furnishes p r i m a r y p o w e r o n its l ines to t h e p r o p e r t y l ine w h e r e i t is m e t e r e d a t a c o m m o n po in t . T h e n b y W B A P l ines , p r i m a r y p o w e r is sen t t o t h e t r ansmi t t e r b u i l d i n g for a i r c o n d i t i o n i n g a n d t r a n s m i t t e r p o w e r . F r o m t h e subs t a t i on a t t h e m a i n b u i l d i n g , service is p r o v i d e d to t o t h e a i r c o n d i t i o n i n g compressors , h e a t exchanger s , m o t o r s , a n d e q u i p m e n t r e q u i r i n g 440-vol t service . T h e s e c o n d a r y b u s feeds a 50-kva t r a n s f o r m e r se rv ing t h e b u i l d ­i n g a n d film l a b o r a t o r y n e e d s ; a 100-kva t r ans fo rmer for r a d i o s t u d i o e q u i p m e n t ; a 150-kva t r a n s f o r m e r for r e g u ­l a t ed p o w e r t o t h e te levis ion e q u i p m e n t ; a 150-kva t r ans ­f o r m e r se rv ing a 2 0 0 - a m p e r e m a i n b r e a k e r t o s tudio 2 l i g h t i n g ; a n d a 2 0 0 - a m p e r e m a i n b r e a k e r to t h e s tudio 1 d i m m e r c i r cu i t . T h e r e a r e t w e l v e 5 0 - a m p e r e sub-breakers o n this c i rcu i t . T h e last 150-kva t r ans fo rmer on t h e s e c o n d a r y b u s feeds t h e 1 2 0 - 2 0 8 vol t , 3 -phase , 4-wire se rv ice to t h e n o n d i m c i r cu i t on t h e s w i t c h b o a r d in s tud io N o . 1 T h e r e a r e , of course , m a n y o t h e r c i rcu i t s fed from t h e

s e c o n d a r y b u s t r a n s f o r m e r s ; for in ­s t ance , a c i r cu i t t o p r o v i d e p o w e r t o t h e r e m o t e t r u c k for ad jus t ing e q u i p ­m e n t w h i l e t h e t r u c k is p a r k e d in t h e g a r a g e .

NEW LIGHTING SWITCHBOARD

Fig. 2. View from catwalk showing original lighting equipment

T H E N E W STUDIO SWITCHBOARD

h a s a c a p a c i t y of 1,800 a m p e r e s . T h e n o n d i m c i rcu i t c o n t a i n s 400-a m p e r e m a i n fuses a n d a m a i n swi tch . T h e r e a r e twe lve 100 -am-p e r e s u b - b r e a k e r s . T h e d i m c i rcu i t c o n t a i n s 2 0 0 - a m p e r e m a i n fuses a n d a m a i n swi tch . T h e r e a r e twelve 5 0 - a m p e r e s u b - b r e a k e r s e a c h feed­i n g a 55-kw W a r d L e o n a r d A u t r a -s ta t d i m m e r . M a s t e r a n d s u b m a s t e r d i m m e r c o n t r o l h a n d l e s a r e p r o ­v i d e d .

" R o t o l e c t o r " swi tches a r e used in t h e n e w s w i t c h b o a r d . A ro to lec to r swi tch is a c o n v e n i e n t m e a n s of c ross -connec t ing a load c i rcu i t t o a n y s u p p l y c i rcu i t . T w e n t y - f o u r

M A R C H 1956 Wygant—Conversion of Studio Lighting 211

Fig. 3 (left). Original switchboard. Fig. 4 (right). New switchboard, showing dimmers at left, rotolector switches at right

ro to lec to r s a r e u s e d — c o r r e s p o n d i n g to t h e 24 s u b c i r c u i t s — 12 d i m a n d 12 n o n d i m . I n al l , t h e r e a r e 140 2 0 - a m p e r e a n d t e n 5 0 - a m p e r e un i t s , e a c h w i t h a b r e a k e r a n d p i lo t l igh t . T w e l v e a m m e t e r s across t h e t o p m e t e r t h e d i m m e r c i rcu i t s to a l low t h e o p e r a t o r t o l o a d t h e d i m m e r s t o t h e i r full c a p a c i t y . T h e s w i t c h b o a r d a n d ro to lec to r s a r e o n a p l a t f o r m e leva ted 3 feet a b o v e t h e s t u d i o floor. T h e v a l u a ­b l e s t u d i o floor s p a c e lost is offset b y t h e c o n v e n i e n c e of a n e a r b y l oca t i on (Fig . 4 ) . A t r e m e n d o u s s a v i n g i n p o w e r h a s b e e n rea l i zed f rom this n e w loca t ion . W i t h t h e n e w l i g h t i n g l oad it w o u l d b e a g r e a t w a s t e t o h a v e nonessen t i a l l a m p s b u r n i n g . T h e n e w s w i t c h b o a r d loca t ion m a k e s i t p r a c ­t i ca l t o k e e p t h e l ights off unless in a c t u a l use . T h e t u r n a n d t i l t con t ro l s w e r e m o v e d w i t h t h e s w i t c h i n g to t h e p l a t f o r m .

LOAD CIRCUITS

U N D E R T H E OLD SYSTEM t h e l oad c i rcu i t s w e r e fed f rom t h e r e l ay con t ac to r s i n t o t h e s tud io in 4 - inch s q u a r e d u c t s

Fig. 5. New lighting layout, showing switchboard at right

w i t h h i n g e d covers . T h e r e was a to t a l of 120 twist- lock r ecep t ac l e s i n c o n n e c t i n g boxes . F o r t u n a t e l y , t h e r e w a s p l e n t y of s p a c e i n these d u c t s t o a c c o m m o d a t e a d d i t i o n a l w i r i n g . T h e l o a d w i r e t o e a c h r e c e p t a c l e w a s d i s connec t ed f rom its r e l a y t e r m i n a l , l e n g t h e n e d , a n d c o n n e c t e d t o its p r o p e r ro to l ec to r t e r m i n a l , t h u s u t i l i z ing mos t of t h e ex is t ing w i r i n g a n d all of t h e exis t ing recep tac les . U n d e r t h e old sys tem a s e p a r a t e n e u t r a l w i r e was c o n n e c t e d t o t h r e e r ecep tac le s . I t w a s necessary to a d d n e u t r a l s so t h a t t h e n e u t r a l of e a c h r e c e p t a c l e w a s ind iv idua l ly fed b a c k to t h e ro to lec to r b o a r d . T w e n t y a d d i t i o n a l 2 0 - a m p e r e twist lock a n d t e n 5 0 - a m p e r e p i n t y p e recep tac les w e r e a d d e d t o these d u c t s a b o v e t h e gr id .

NEW FIXTURES

T H E 18 TELEVISION ASSOCIATES INCANDESCENT BANKS in

u se s ince 1948 w e r e r e t a i n e d . T h e s e c o n t i n u e d to use b o t h PAR-38 a n d R-40 t y p e l a m p s o n s e p a r a t e c i rcui t s a n d r e ­

t a i n e d t he i r t u r n a n d ti l t con t ro l s . T h e 15 s l iml ine fluorescent f ixtures w e r e t a k e n d o w n — n o t b e c a u s e of a n y a d v e r s e e x p e r i e n c e w i t h t h e l igh t q u a l i t y , b u t b e c a u s e of the i r phys ica l size a n d s p a c e l imi t a t ions (Fig . 5 ) . Fifty 18- inch scoops w e r e a d d e d , e a c h us ing 2 -kw c lea r PS-52 g e n e r a l service l a m p s . E i g h t e e n scoops w e r e h u n g o n i n d i v i d u a l p a n t a -g r a p h s . T o m a k e it possible to l ower these scoops to e y e level t h e p a n t a g r a p h s w e r e ins ta l led o n a 1-i n c h p i p e gr id s u s p e n d e d 3 feet b e ­low t h e p e r m a n e n t g r id . T h e re­m a i n i n g 32 scoops w e r e h u n g on p e n d a n t c l a m p s w i t h a 4-foot h e i g h t a d j u s t m e n t . T h e s e in t u r n w e r e h u n g in pa i r s f rom t u r n i n g sp indles s imi la r t o t h e t u r n i n g devices on t h e Te lev i s ion Associates te le l ights . T h e s e w e m a d e u p f rom s p a r e p a r t s a n d 3 / 4 - i n c h p i p e . T h i r t y 8- inch Fresne l spots w e r e a d d e d for b a c k

278 W y gant—Conversion of Studio Lighting E L E C T R I C A L E N G I N E E R I N G

a n d k e y l igh t ing . T w o - k i l o w a t t G-48 m o g u l b ipos t l a m p s a r e b e i n g used i n these spots . F o r spec ia l effects, five 16- inch F resne l spots us ing 5-ki lowat t m o g u l b ipos t l a m p s w e r e a d d e d . F o r s imi l a r u se , six 6- inch str ips e a c h c o n t a i n i n g twelve 150 w a t t R-40 s p a t l a m p s ; t w o 750 w a t t b o o m l igh t s ; a n d t w o 8-inch, 2 -k i lowat t p a t t e r n p ro jec tors w e r e a d d e d . T h e r e is n o w 60 w a t t s p e r s q u a r e foot as c o m p a r e d w i t h 18.5 prev ious ly used . (See F ig . 6 ) .

CONSIDERATIONS

T H E R E W E R E SEVERAL c o n s i d e r a ­

t ions w h i c h p r o m p t e d t h e types a n d n u m b e r of f ixtures, t h e c o n t r o l e q u i p m e n t , a n d t h e m e t h o d of in ­s ta l la t ion . Firs t , i t w a s n o t e c o n o m i ­cal ly feasible t o s c r a p t h e inves t ­m e n t in t h e te le l ight i n c a n d e s c e n t 12 l a m p b a n k s . A l t h o u g h these fix­tures a r e old a n d t h e l igh t o u t p u t n o t as c o n t r o l l a b l e as somet imes m i g h t b e des i red , t h e y d o p u t ou t a l a r g e q u a n t i t y of l ight , o n e of t h e essentials for color l i gh t ing . T h e r e f o r e , t h e first c o n s i d e r a t i o n w a s t h e i n t e g r a t i o n of t h e i n c a n d e s c e n t fixtures a t least , if n o t t h e f luorescent f ixtures, w i t h t h e n e w l igh t ing sys tem.

T h e second c o n s i d e r a t i o n w a s t h e p r o g r a m m i n g . I t was p l a n n e d to s t a r t f rom t h e first w i t h 5 V 2 h o u r s p e r week of l ive s tud io p r o g r a m s . T h i s m a d e it a d v i s a b l e t o p r o v i d e o n e e n d a n d o n e s ide of t h e s t u d i o wi th 400 foot cand le s of l igh t a t a n y o n e t i m e . F u r t h e r , it was cons ide red des i r ab le t o b e a b l e t o swing t h e l igh t qu ick ly f rom o n e s ide of t h e s t u d i o t o t h e o t h e r d u r i n g a p r o g r a m . I t works this w a y in a c t u a l p r a c t i c e : S c e n e 1 is a l o n g t h e wes t w a l l — w h e n scene 2 is o n t h e a i r f rom t h e s o u t h e n d of t h e s tud io , t h e l ights c a n b e r ead jus t ed f rom t h e wes t s ide over t o scene 3 a l o n g the east wa l l , b y o n e m a n . T h i s l eads to t h e t h i r d c o n s i d e r a t i o n — t h a t n o a d d i t i o n a l p e r s o n n e l w o u l d b e a d d e d to t h e staff t o t a k e c a r e of t h e l igh t ing . O n e m a n is respons ib le for t h e l i gh t i ng a n d l i g h t i n g e q u i p m e n t m a i n ­t e n a n c e . T h i s m a n h a s o t h e r du t i e s , b u t before a n d d u r i n g the color shows h e devo tes his e n t i r e t i m e to l i gh t ing . T h i s is t h e r eason as m a n y fixtures as possible h a v e t u r n a n d ti l t ad jus tmen t s c o n t r o l l a b l e f rom a c e n t r a l l oca t ion .

T h e n e x t cons ide ra t i on invo lved a c c u r a t e in tens i ty c o n ­t rol . I t was des i red to l igh t all sets w i t h a u n i f o r m l igh t level of 400 foot cand le s p lus o r m i n u s n o m o r e t h a n 25 foot cand le s . L i g h t i n g effects, p a r t i c u l a r l y those i nvo lv ing d i m m i n g , h a v e a lways b e e n i m p o r t a n t t o th is s t a t ion a n d it was des i red to c o n t i n u e or even e x p a n d t h e use of effects. T o m a k e t h e l i gh t ing as u n i f o r m as possible as wel l as m a k e possible a n y effects t h e d i r ec to r s w o u l d l ike t o t ry , t h e ro to lec tor b o a r d a n d t h e d i m m e r s w e r e i n c l u d e d in t h e p l ans . A n e w c o n t r o l sys tem was necessary in a n y case , it was physica l ly imposs ib le t o e x p a n d t h e old s w i t c h b o a r d a n d re lay system to c a r r y t h e a d d i t i o n a l load , even if a n y ­o n e h a d des i red to c o n t i n u e t h e old sys tem.

Fig. 6. New lighting layout

A n e x t r e m e l y i m p o r t a n t c o n s i d e r a t i o n w a s t h e b u d g e t . T h e m a n a g e m e n t w a s , of cour se , wi l l ing t o s p e n d t h e a m o u n t necessa ry t o p r o v i d e a g o o d co lo r p i c t u r e . S o m e effects fall u n d e r th is c a t e g o r y , b u t l a r g e n u m b e r s of fancy gadge t s a n d accessories d o n o t .

W e a r e n e v e r c o m p l e t e l y satisfied w i t h w h a t w e h a v e — t h e r e a r e a lways n e w t h i n g s o n t h e m a r k e t , o r c h a n g e s , or expans ions t o cons ide r . As soon as funds a r e ava i l ab le , p l a n s cal l for conve r s ion of a n o t h e r s tud io , 30 b y 40 feet, f rom b l ack a n d w h i t e t o color , as wel l as a d d i t i o n a l spots for u se as b a c k l igh t i n t h e l a r g e s t u d i o a n d possibly sub­s e q u e n t conve r s ion to p i n - t y p e c a b l e c o n n e c t o r s .

Cigarette Lighters Ordered for USAF

T h e c o m m o n a u t o d a s h b o a r d c i g a r e t t e l igh te r has i n v a d e d t h e r e a l m of e lec t ron ic war f a r e , as a bu i l t - in p a r t of a c o m p l e x n e w g r o u n d - b a s e d U n i t e d S ta te s A i r F o r c e a i r defense sys tem in d e v e l o p m e n t h e r e .

T h e l igh te r h a s a d i s t inc t ly scientific p u r p o s e in t h e c o m p l e x , classified e l ec t ron ic e q u i p m e n t b e i n g bu i l t u n d e r a m u l t i m i l l i o n - d o l l a r c o n t r a c t b y G e n e r a l Elec t r ic ' s h e a v y m i l i t a r y e lec t ron ic e q u i p m e n t d e p a r t m e n t .

E n g i n e e r s say a n o p e r a t o r , s c a n n i n g t h e sys tem's g lowing i n d i c a t o r r a d a r scopes for h o u r s in semida rkness , cou ld b e t e m p o r a r i l y b l i n d e d b y t h e flare of a m a t c h o r pocke t l i gh t e r w h e n l i g h t i n g a c i ga r e t t e . F u r t h e r m o r e , his h a n d s m u s t b e free t o w o r k t h e d o z e n s of k n o b s , swi tches a n d b u t t o n s o n t h e c o n t r o l p a n e l .

A c c o r d i n g l y , t h e bu i l t - i n l i gh t e r w a s o r d e r e d as p a r t of a " h u m a n e n g i n e e r i n g " p r o g r a m , t o k e e p t h e o p e r a t o r as u n d i s t r a c t e d as possible .

M A R C H 1956 Wygant—Conversion of Studio Lighting 279