‘Phonotrix’ High speed keyer - WftW

1 Wireless for the Warrior - Volume 4 Supplement, Chap. 91- 1 Page 1 of 2. WftW Volume 4 Supplement, Chapter 91. ver Nov SUMMARYO rganisation:Central Intelligence Agency. (Germany W)Design/Manufacturer:E. Voelk KG, Nurnberg, Germany.(Trix United Toy Factories);Modification: of Introduction: Probably :High speed Morse keyer for Supply: 6V DC at (cm):Height 9, length , width : Recorder only less :Morse key, 75mm diameter tape reel con-taining about 65m tape, empty reel, earphone, four D cells. This WftW Volume 4 Supplement is a download from It may be freely copied and distributed, but only in the current phonotrix was a commercial toy tape recorder adopted andmodified for use as high speed Morse keyer . This cheap and readilyavailable miniature tape recorder appeared very suitable for this pur-pose: lightweight and small in size; use of standard tape; powered byonly four D cells and a continuous regulation of speed from 3 to15cm/sec.

2 Recorded messages in Morse code at a tape speed ofslightly higher than 3cm/sec would playback at a speed of 15cm/sec,about 4 times the original speed . Recorded and used tapes could beerased and used again. Known is the use of the phonotrix with the Modular transmitter-receiver. (Described in chapter 54).Modifications and additions to the original phonotrix were an AFtone generator for recording Morse code messages keyed by an exter-nal hand speed Morse key. After rewinding the tape and switched toplayback, the AF output of the recorder was connected to a tone de-tector circuit and keying relay. Connected to the transmitter keyingcontacts, and when started to play with a tape speed control set tomaximum, the transmitter was keyed at high speed .

3 See the block di-agram on the next :- With thanks to Detlev Vreisleben, DC7KG, Germany, who kindly supplied all the photos, technical and historical page of an original commercial sales leaflet for the phonotrix , made by Trix United Toy hand side panel of the phonotrix : Microphone (red)and loudspeaker (blue) sockets (left), playback volume con-trol (centre) and Record/playback switch (right). The twoaudio sockets were not used in the modified high speed Morse keyer connected to a Modu-lar transmitter receiver, used by agents of the AmericanCIA. The picture above was a taken of a set captured froma CIA agent operating in the GDR. phonotrix High speed keyerCountry of origin:Ger. for the Warrior - Volume 4 Supplement, Chap. 91- 2 Page 2 of 2.

4 WftW Volume 4 Supplement, Chapter 91. ver Nov. 2015. This WftW Volume 4 Supplement is a download from It may be freely copied and distributed, but only in the current diagram of the original commercial phonotrix miniature toy taperecorder. A number of modifications and additions were required tomake the recorder suitable for use as a high speed taken from the original userhandbook with functional expla-nations of the various controls. 1 Microphone socket (red) 2 Loudspeaker socket (blue) 3 Volume control 4 Record-playback switch 5 Play/record-stop-fast rewind 6 Tape speed control 7 Full reel capstan 8 Empty reel capstan 9 Bottom cover10 Full reel11 Empty reel12 Head and roll cover Tape guide capstan14 Tape guiding15 Erase magnet16 Record/playback head17 Rubber pinch roll18 Driving capstan AF tonegenerator TonedetectorKeyingrelayMorse key.

5 Socket BMicrophone inputRecorder AF outTo transmitter. Plug ATo receiverAF EBlock diagram of additions to the originalPhonotrix circuit view of amodified Phonotrixshowing the con-nectors E and C,and the existingexternal 6V of a modified Phonotrixready for recording a Morse code mes-sage. (Left)Socket A was for side tone of keyingduring recording a message and check-ing in playback or when connected tothe receiver listening to the corre-sponding main station via plug B connected the Morse C or D connected to the transmit-ter keying contacts.