Nachtfee discussions

Created on 2 January 2012

Status: 6 January 2012


On request of Mr. Helwig Schmied this discussion page is being created.


Nachtfee working hypothesis 3, by Helwig Schmied



On 4 January we received from Hans Jucker the following drawing

I trust that Hans Jucker's drawing is self-explaining

Please double click at this drawing as to open it in pdf



On 6 January 2012 I would like contributing myself (AOB)


Hypothesis 8 AOB

 After being engaged in the Nachtfee survey since 12 November 2011, and having expressed my various opinions on what Nachtfee technology is about, time has come to express how the Nachtfee data might have been conveyed towards an aircraft.

 We have noticed that our investigation on 4 January (  brought to daylight how de “Freya-Polwender” signal might have looked like (I believe, that our signal still is more or less faulty).

 I know, that calling this data line “Freya-Polwender” is not entirely accurate, but it shows what kind of signal we are dealing with. The term ‘Polwender’ does imply only: that by means of a double-pole-switch at the front panel the two data wires is at will interchanged. This does only make sense, when there is a sort of data coherence. Hence, the phase of the input pulse provided must have been correlated to the Nachtfee data output signal. For better understanding – the data line is completely kept free from ground; hence, we are dealing with a two-wire data line.

My second guess - it does make sense using a sinusoidal carrier with some data fit onto it (superimposed). This sinusoidal carrier is then to be transmitted towards the accordingly equipped aircraft. In this case allowing that this sinusoidal signal is in some way fed onto the CRT deflection system inside the aircraft. However, fading and eventually Doppler shift might cause vector data deviation.

I have not a clear judgement how this principle could cope with the frequency wobbling inside the FuG25a aircraft transponder receiver. It might cause a sort of data sampling, but its audio phase will not be shifted. Not yet clearly measured is the exact frequency of the sinusoidal data signal versus the impulse phase. I would not be surprised when this is about the same as the pulse recurrence frequency send from the Freya or EGON system towards the Nachtfee order apparatus.

The Nachtfee 220 V ac mains connector is accompanied by the information that the source is, or has to be, stabilised. My guess, they might themselves have encountered how delicate the internal free running oscillators respond onto environmental conditions.

It is also likely, that Nachtfee and EGON were operated in the same cabin. Paul Reuvers suggested already op 12 November 2011, that the strange way the moveable order section (and photo 2) is mounted might point to the path that some personnel must use the flexible space (moveable about 45 degrees) for entering or leaving. This is a rather logical conclusion, as we never have seen elsewhere a comparable like apparatus layout. When we look at the Würzburg apparatus arrangement, then we also recognise similar way of thinking, but now being fit to operational conditions. CRTs placed under different angles and that like.

 This hypothesis is, as the word expresses a hypothetical estimation, which, nevertheless, might be incorrect. However, this is the way it goes.

Arthur O. Bauer

6 January 2012  


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By Arthur O. Bauer



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