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Build 'Cyclops' a 1 tube radio using a magic tuning eye
For those who have a spare 6e5 magic eye lying about, this is a novel functioning eye regenerative set using the eyes triode as detector, and the aperture as a tuning indicator that you can build in a couple of evenings. A switch lets you switch the aperture on or off which will improve the performance of the receiver. This is not a serious receiver, the low mutual transconductance (amplification factor, or gain) of the eye sees to that, but rather more of a neat little gimmick set, particularly if built into a perspex case. 

I have not built this circuit yet, (I'll add photos if I do), but I do notice a something straight away, your not going to get far with just 2v on the filament as suggested in the below circuit, use 6v (6.3) here, unless you have a 2E5 2v eye which is more likely what Harold really used originally. A 6h5, 6g5, 6t5 or 6u5 should all work but apertures will differ. A 12v 1629 tube can also be used if a voltage doubler is used, or 12v (12.6)  filament supply (A) is used, on heaters. As with these sets, there's plenty of room for experimentation, nothing too particular value or voltage wise, try anything up to 5megs or so in the grid leak.  Any broadcast band ant.rf coil may be be used or modified, or you may want to wind you own, plenty of info on the net or email me for data. For more info on magic eyes in general go here . Please submit your effort so we can all enjoy it.
 Caution: voltages in this project may exceed 200v  this page is dedicated to Harold Mueller



If you want to get started on a simple set that performs much better and just on battery voltages, check out a circuit from Fran Golden by downloading 1-tube radio.pdf, try our hikers circuits here, or check the project archives

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