If Test Procedure.

unit 4 to 550 mc (the center of the low-band

c. Rf Chart. When the tests in b above

frequency range), and proceed as indicated

show that the trouble is not in the if. am-

in the chart below. After the tests of the

p l i f i e r , the if. step attenuator, nor in the

l o w - b a n d rf tuner have been checked out

i f . preamplifier, proceed with the tests

s a t i s f a c t o r i l y , rotate the band switch to

listed in the chart below. Use tuning unit

700-1,000 mc; then set tuning unit 4

4 signal generator (para 65) with 1,000-ops

s i g n a l generator and the TUNING dial of

modulation. Since tuning unit 4 uses band

s w i t c h i n g , first rotate the band switch to

tuning unit 4 to 850 mc (the center of the

h i g h - b a n d frequency range) and perform

400-700 mc; then set tuning unit 4 signal

t h e tests indicated.

generator and the TUNING dial of tuning

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