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The Gruner Schematic

Below I have reproduced a photograph of the original Gruner Schematic as taken by Jeff Garff, Bob Harrison's corrected engineering drawings of the same, and finally a PDF file containing my modern redrawing of the schematic. Please note that we don't have all the component values, they were not on the original schematic. Despite this, it is easy to see that it is in fact a classic Hartley MOPA type design almost identical to the 1939 Beam Rays machine in the output stage. The modulator section is very strange but clearly would produce a modulation in the low audio range.

There are some notes on the original schematic in John Crane's handwriting. In the lower left corner is a functional diagram of a Hartley oscillator. From the notations on it, it is clear that someone was trying to explain to someone else that the circuit was a true Hartley. The fact that it is a Hartley is not obvious, as in the case of the 1939 Beam Rays machine, because the plasma tube itself forms part of the capacitive tuning loop for the output. If a capacitor were substituted for the plasma tube the design would become a classic Hartley.

In the lower right hand corner of the schematic are some further notes by Crane which give specifications of the plasma tube and some other notes as follows:

The plasma tube is described as being a phanotron type tube, a 7 inch diameter, 3 litre Pyrex Flask, with electrodes 1 1/4 inches in diameter placed 2 inches apart in Helium at 12mm pressure. I believe this is the definitive description of the early Rife/Hoyland plasma tubes and this specification is fairly critical for optimum operation.

The Crane notes go on to say: By John F. Crane 3-5-51 (Verne Thompson's name also appears to one side). From O.C. Gruner MD's records from Milbank Johnson and Rife and Hoyland's conception of Rife Ray tube Frequency Instrument - 1951

I present the data below, more will be added as I get time.

Photo of Original Schematic

Bob Harrison's Corrected Engineering Drawings

Modern Version by Aubrey Scoon (PDF format) is linked here.