Y-Gerät

[Panrock]

One 'mistake' I can think of is that, since the strongest signals were on 42 MHz, they would have been right at the edge of the lower vision sideband and not very well received.

Steve

[Panrock]

And another thought. Weren't the Germans being a bit 'thick' not realising what was going on? The Alexandra Palace tower would have seemed to be an attractive bombing target. Maybe it was protected by barrage balloons and these were an effective defence?

Steve

[ppppenguin]

Hitting a pinpoint target like AP was a big ask with any of the German beam systems. Theoreticallly possible but not easy. Our Oboe system could do it but that was much later in the war.

[peter scott]

Hitting a pinpoint target like AP was a big ask with any of the German beam systems. Theoreticallly possible but not easy.

Clearly a stick of bombs did hit the terrace!

   

Peter

[Panrock]

One 'mistake' I can think of is that, since the strongest signals were on 42 MHz, they would have been right at the edge of the lower vision sideband and not very well received.

... which implies the strong signals, at least, would perhaps been better heard as audio tones over the sound receiver.

Now the EMI 702 (and 901) sets have a tunable sound receiver, quite selective, prone to drift, and based around a fairly low IF for a VHF receiver... (without checking) do I recall this is 1500 KHz? 

Question: What is the pick-up frequency range of this receiver? Could the tuning knob have been twiddled and the 42 MHz jamming signals been picked up?

Steve

[peter scott]

Well mine tunes over 41.025 MHz to 41.761 MHz with user control but I dare say it could move further if I tweaked the oscillator coil.

Peter

[Panrock]

Thanks for checking Peter. So if the 41.5 MHz setting happened to be off-centre, 42 MHz should have been within range. 

It's amazing to think that eighty years ago you could have used your new-fangled television set to tune in to the electronic warfare going on in the skies above. Like something out of H.G. Wells...

Steve