Section IV
Paragraphs 4-14 to 4-20
4-18. The 27.000 to 33. 975-mc signal from V1504 is
signals are mixed and the sum frequency, 27.000 to
coupled through C1520 to the grid of r-f quadruple
33.975 mc, is passed through T1502 and fed to r-f
V1505. The signal is amplified and distorted by V1505
amplifier V1504. Coils L1503 and L1504 are tuned in
and due to the distortion of this signal, a signal rich
28 steps of 250 kc each by the outer knob of the MEGA-
in harmonics appears in the output. The plate circuit
CYCLES control. The band pass of T1502 is suffi-
of V1505 is tuned to the fourth harmonic of the input
ciently wide to cover the megacycle spread of V1501.
signal by part of 21501, a tuned circuit comprising
Trimmers C1511 and C1514 are used to adjust T1501
L1506, C1523 and C1524, and the frequency of the out-
at the upper frequency limit.
put will be in the range of 108.0 to 135.9 mc. This
output is fed to r-f amplifier V1506. Coil L1501 is
4-15. R-F AMPLIFIER V1504.
(See figure 4-6. )
tuned in 28 steps of one megacycle each by the outer
knob of the MEGACYCLES control. The band pass of
4-16. The 27.000 to 33. 975-mc signal from V1503 is
the tuned circuit is sufficiently wide to cover the meg-
coupled through C1515 to the grid of r-f amplifier
acycle spread of V1501. Trimmer C1523 is used to
V1504. Here the signal is amplified and delivered to
adjust the tuned circuit at the upper frequency limit.
r-f quadrupler V1505. Part of 21501, comprising
L1505, C1519 and C1518, forms a tuned circuit that
4-19. R-F AMPLIFIER V1506.
will pass a frequency in the range of 27.000 to 33.975
mc depending on the setting of the MEGACYCLES con-
(See figure 4-8.)
trol. The band pass of this tuned circuit is sufficiently
wide to cover the megacycle spread of V1501.
r-f chassis. The 108.0 to 135. 9-mc signal from
4-17. R-F QUADRUPLER V1505.
V1505 is coupled through C 1525 and grid current
(See figure 4-7.)
limiting resistor R1566 to the control grid of V1506.
