Rebecca Mk8  TR 8193 interrogator  ( 1956)

For Eureka or  Blind Approach beacons

ARI 23013


A beacon interrogator system was developed in WWII to home-in on small transportable beacons (Eureka) or  on a runway centre-line beacon (BABS). The aircraft part is named Rebecca ( I am searching). This site is about the last one of the Rebecca series, the Mk8.

The first technician courses on Rebecca 8 was in June 1956

Philips Sweden made an improved  version for the Swedish Airforce, the  PN-50


The components of the aircraft part are :

Transmitter - receiver      TR8193 (10D/19594);

Range  and  heading  indicator           (10AF/530);

Control  unit               type  8197    (10L/16264);

The aircraft aerial was a yagi or a slotted aerial


          Circuit description and diagrams are here


The ground beacon (known as Eureka) was mainly the US

RT-44 / PPN1 (1943 ), or RT-37 / PPN2 (1945 ).

This beacon was dropped a few hours before equipment or crew were dropped.


The indicator showed the  distance to the beacon on a 20 or 200 nm scale, as well as the course deviation on a single instrument. Previous Rebecca systems had a CRT which required a navigator.


The control panel allows the selection of 8 preset frequencies for transmit and receive ( and their setup in the range 214-230 MHz), and six modes of operation :

   BAH    Beam Approach Home ( internal preset freq.)

   BAT     Beam Approach Tuning ( set with TX and RX knobs)

    20        20 nautical miles range on meter  (   ,,  )

   200      200 nautical miles range on meter  (  ,,   )

    SB      Standby  (Heaters only)

  OFF      Rebecca off


Further toggle switches

· CODE :  audible morse code from beacon on/off,

· Strobe :  initialize a strobe cycle

· O/R—H   Omni range or homing antenna


Range meter and control pictures courtesy  GBairspares

I made a testunit for the Rebecca Mk8 system.


T.R. 8193  Transmitter-Receiver  Rebecca Mk8