B737 Radio Tuning Panel

RTP
P8 AFT ELECTRONICS

Frequency Transfer Switch

  • Push:
    • Transfers the STANDBY window frequency to the ACTIVE window and tunes the selected radio to the new active frequency.
    • Transfers the ACTIVE window frequency to the STANDBY window.

Frequency Indicator

  • ACTIVE: Displays the tuned frequency of the selected radio.
  • STANDBY:
    • Displays the preselected or previously tuned frequency of the selected radio.
    • Displays DATA if the selected radio is in the data mode.
    • Displays a six-digit frequency in 8.33 KHz spacing.

Radio Tuning Switch

  • Push:
    • Selects the VHF or HF radio to be tuned.
    • The tuned frequency is displayed in the ACTIVE frequency indicator.
    • The standby frequency is displayed in the STANDBY frequency indicator.

Radio Tuning Panel OFF Switch

  • Push:
    • Disconnects the panel from the communication radios.
    • The switch illuminates (white).

HF Sensitivity Control

  • Rotate: Adjusts the sensitivity of the on-side HF receiver.

Radio Tuning Light

  • Illuminated (white): Indicates the selected radio.

Offside Tuning Light

  • Illuminated (white):
    • The radio normally associated with this panel is being tuned by another radio tuning panel, or
    • The radio tuning panel is being used to tune a radio not normally associated with this radio tuning panel.

Frequency Selector

  • Rotate: Selects frequency in the STANDBY frequency indicator:
    • The first digit is always 1.
    • The outer selector changes the second and third digits in 1 MHz increments.
    • The inner selector changes the fourth, fifth, and sixth digits in 8.33 KHz increments.
    • For airplanes with ACARS, tuning above the maximum or below the minimum frequency displays DATA in the Frequency Indicator.

VHF TEST Switch

  • Push:
    • Removes the automatic squelch feature, permitting reception of background noise and testing receiver operation.
    • Improves the reception of weak signals.

AM Light

  • Illuminated (white): HF AM is selected.
  • Extinguished: HF USB is selected.

AM Switch

  • Push: Sets the AM (amplitude modulation) or USB (upper sideband) mode for the selected HF.