First, Second, and Third Rf Amplifiers V102, V103, and V104 on Transmit

Figure 18. Second transmitter mixer, V101, schematic diagram.

and L102. J103 is a test point for measur-

prevents the dc plate voltage on V101 from

ing the plate voltage or the 20.0- to 29.9-

being grounded through Z101 (fig. 5) and

mc signal applied to the plate of V101. Rf

couples the 225.0- to 399.9-mc from the

choke L103 and bypass capacitor Cl04 de-

plate of V101 to first rf amplifier V102.

couple rf from the +125-volt dc supply.

Capacitor C102 grounds rf at the grid of

53. First, Second, and Third Rf Amplifiers

V101. Resistors R101 and R102 are the

V102, V103, and V104 on Transmit

grid-leak circuit to ground. Jack J104 is

a test point for measuring grid bias on

V101. Bypass capacitor C101 provides a

Coupling capacitors C105 and C110 cou-

l o w - i m p e d a n c e path to ground for rf

ple the rf signal to the cathode of V102. The

signals. Resistors R103 and R114 provide

rf signal receives three stages of rf ampli-

t h e correct termination for injection

fication and is applied to transmitter

cables W101 and W4. On transmit, the +26

driver V105 (para 55). The rf amplifiers

vdc from K601 energizes R102.

function as described in paragraphs 13

c. The 200- to 370-mc uhf injection fre-

through 15 with the following exceptions:

quency and the 20.0- to 29.0-mc first if.

a. Antenna relay K101 energizes (con-

are heterodyned in V101 to produce an out-

tacts 2-3 open) to remove the directional

put rf within the 225.0- to 399.9-mc range.

coupler from the input circuit of first rf

(The band of frequencies between 220-225

amplifier V102.

mc is not used.) Blocking capacitor C105