The radio systems depicted here are representative of those installed on Canadian Mosquito Bombers type B MK XX and FB MK-21 aircraft. I have not included the block diagrams for the radio systems because they are too large for my scanner. From the drawings it appears there were two basic radio configurations. One version was used for aircraft based overseas and while ferrying. The other version was for aircraft based in the UK. The obvious difference is the elimination of the MN26 radio compass in the UK version but there were other differences. Since the aircraft was of made entirely of wood, this permitted the installation of inboard radio antennas which helped to reduce the parasitic drag on the airframe.

In the equipment illustrations I have identified the various pieces of equipment starting from the upper left hand corner and going clockwise.

My thanks are extended to Andre Guibert who loaned me the source material which made this section of the Web page possible.

ARI 5083 & ABK1 Receiver - System Drawing

Receiver, Transmitter and Radio Compass - System Drawing

SCR 522 and A1271 Receiver - System Drawing

Pilot's Controls

Port side view.
Indicates: M122A Station Box; BC602 Command Set Control.

Radio Apparatus Control Panel

Port side view.
Indicates: MT51C Control Unit; 3952 Coupling; MR15 Crank; MN28C Control Unit; MT-11B Telegraph Key; MI-22A Station Box; MP28BA Power Supply; MR-9B Control; MN22A Azimuth Indicator.

Just to the right of the MN28C control unit is the armored backing for the pilot. The navigators seat was made from plywood and was fitted a few inches back from the pilot's position on the starboard side. During operations, the navigator had to lean in the back of the pilot to operate the radios and GEE scope (where fitted) plus operate the fuel tank selectors. The setup was so cramped, it makes one wonder whether the navigator's qualification required the ability to send Morse with the left hand.


View Looking aft.
Indicates: RA10DB Receiver with transmitter removed from the foreground; MT53C Loading Unit.

The RA10DB receiver band coverage is as follows:

Band 1:  150-400 kc
          2:  400-1100 kc
          3:  2.0-5.0 Mc/s
          4:  5.0-10.Mc/s

Rear Fuselage - Lower View

View looking aft and lower.
Indicates: SCR522 unit; 359 Socket Test Position; A1271 Amplifier.

Rear Fuselage - Upper View

View looking aft and upper.
Indicates: Type 66AAV Antenna; MN20A Loop Antenna; MN26C Compass; SCR522; JB29A Junction Box.

TA12 Transmitter Installation

The TA12C photo shows the view looking aft.
Indicates: TA12C Radio Transmitter; Junction Box #R3000-27B; Junction Box #R3000-26B; Plugs into power supply; MT53C Antenna Loading Unit.

The TA-12 transmitter family was conservately rated at 40w. There were four channels, each having its own separate oscillator. The output of each oscillator was tuned by one the four knobs down the left hand side.   The following ranges were applicable for the TA 12B:

Channel  1:   300-600 kc
                2:    3.0 - 4.8 Mc/s
                3:    4.0 - 6.4 Mc/s
                4:    4.37 - 7.0 Mc/s

Modes: CW/MCW/Phone.

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July 6/11