Table 3-2. Crystal Frequencies and Operating Bands

TM 11-5820-554-12

frequency is half the sum of the lower edge of the

crystal mounting board and a front panel switch to

desired band and 3.155 MHz. For example:

allow selection of either board. The crystal-mounting

14.4 + 3.155 = 8.7775 MHz

board for extra-band operation is located on top of the

chassis. If amateur band operation is not needed,

The plate circuit of the oscillator is tuned to twice the

extra-band crystals may be substituted in the crystal-

crystal frequency when required injection frequencies

mounting board under the chassis. BE SURE the

are this high.

crystals are plugged into appropriate sockets

according to table 3-2 and figure 3-6. The transmitter

CAUTION

Avoid transmitter operation between 5.0 and

can be operated at other frequencies outside the

6.5 MHz.

In this range, the second

specified amateur bands or at other 10-meter

harmonic of the variable IF is nearly the

frequencies by plugging the proper crystals into the

same as the desired frequency. In the

mounting boards. Mark the desired lower band edge

transmit function, some of this energy will

information on the white card in the BAND switch

pass through the tuned circuits and become

windows. Make sure this information is marked in the

spurious emissions.

appropriate switch positions.

(3) Plug substitute or extra crystals into the

b. Adjustment of Tubbed Circuits. For

appropriate socket on the mounting board according

operation outside amateur bands, disregard amateur-

to BAND switch position and total coverage columns

band markings on the EXCITER TUNING and P.A.

in table 3-2. The example given in (2) above calls for

TUNING scales and use logging scales (fig. 3-5).

placement of the crystal in one of the sockets marked

Operation at frequencies outside the amateur bands

C. If two additional 10-meter crystals are used, they

will result in slightly decreased receiver sensitivity and

must be plugged into the sockets marked E. Table 3-2

transmitter pa grid drive, unless the tuned circuits of

lists crystal socket designations, switch positions

the transceiver are retained to peak their responses in

(BAND), crystal frequencies, and frequency range

the desired portion of the high-frequency spectrum.

limitations. The KWM-2A is equipped with an extra

Table 3-2. Crystal Frequencies and Operating Bands

KWM-2/2A

Crystal

Operating frequency

frequency

(MHz)

(kHz)

Bandswitch setting 1A, 2A, or 3A

4.0 to 4.2 ------------------------------------------------------------------------------------------------------- 7155.0

4.2 to 4.4 ------------------------------------------------------------------------------------------------------- 7355.0

4.4 to 4.6--------------------------------------------------------------------------------------------------------- 7555.0

4.6 to 4.8 ------------------------------------------------------------------------------------------------------- 7755.0

4.8 to 5.0 ------------------------------------------------------------------------------------------------------- 7955.0

Bandswitch setting 1B or 2B

6.6 to 6.8------------------------------------------------------------------------------------------------------ 9755.0

6.8 to 7.0 ------------------------------------------------------------------------------------------------------- 9955.0

7.0 to 7.2. ------------------------------------------------------------------------------------------------------ *10155.0

7.2 to 7.4 ------------------------------------------------------------------------------------------------------- *10355.0

7.4 to 7.6 ------------------------------------------------------------------------------------------------------- 10555.0

7.6 to 7.8 ------------------------------------------------------------------------------------------------------- 10755.0

7.8 to 8.0 ------------------------------------------------------------------------------------------------------- 10955.0

8.0 to 8.2 ------------------------------------------------------------------------------------------------------- 11155.0

8.2 to 8.4 ------------------------------------------------------------------------------------------------------- 11355.0

8.4 to 8.6 ------------------------------------------------------------------------------------------------------- 11555.0

8.6 to 8.8 ------------------------------------------------------------------------------------------------------- 11755.0

8.8 to 9.0 ------------------------------------------------------------------------------------------------------- 11955.0

9.0 to 9.2 ------------------------------------------------------------------------------------------------------- 12155.0

9.2 to 9.4 ------------------------------------------------------------------------------------------------------- 12355.0

9.4 to 9.6 ------------------------------------------------------------------------------------------------------- 12555.0

See footnote at end of table.

3-12