The klystron

During his time at Stanford, Russell built up friendships; and one especially, with a physicist called Bill Hansen, was to blossom. Hansen worked on X-ray phenomena and microwaves. Early in the Second World War his teaching notes were classified and used at the famous MIT Radiation Laboratory, where much of the American work on radar was performed and co-ordinated. Before that, however, with Russell Varian he speculated on how to get high velocity electrons without spending a lot of money. The result of Hansen's work was the rhumbatron (named after the rhumba dance), a cavity resonator which was to feature in the invention of the klystron.

When Russell arrived at the home laboratory, Sigurd and Eric were busy developing earlier ideas and still hoping that Russell would invent "the big one". Cities were being bombed in Spain and China, and aircraft detection was high on Sig's list of priorities¹⁴. They knew that short wave radiation would be suitable but there was no way of generating the high powers required. Of course they did not then know of the secret military work on pulsed radar.

Russell recognized the need for a resonator and thought of Bill Hansen's rhumbatron. He and Hansen talked it over in May 1936 and Russell developed his ideas further. In February 1937 he had the design for a microwave tube and sought permission to use Hansen's resonator. Other ideas developed and Russell came to realise that completion of the project was beyond the resources¹⁵ of their little laboratory.

Sigurd's drive and determination saved them. He believed this was the "big one". Now he proposed to use the laboratories of Stanford University. Russell hesitated. Sig did not. By the end of April they had an agreement with the university that it would provide facilities, the right to consult with staff, a research grant of $100, but no salaries. In return, Stanford got equal shares of any financial return. It was a good deal all round.

Celebration

Once they had started, many ideas and variations on ideas tumbled out of their minds¹⁶. So much so that on June 5, 1937, Russell decided to sit down and classify them all to ensure nothing was overlooked. It was whilst doing his classification that the fundamental idea for the klystron, the velocity grouping or bunching principle, struck him. Sig remembered the date clearly: it was the day be blew the main breaker in the university power house.

With a determined struggle they completed the design and built the first klystron, overcoming many problems on the way. The completion of the first hand-filed hexagonal grids called for a celebration. Building their own detection and measuring equipment proved to be another important problem; and solved it was. In two months the Model A 10cm klystron, encased in a vacuum bell jar, was working - intermittently - on August 19, 1937. By the 30th the device had been rebuilt and gave continuous operation at 13cm. It had cost $50 of Stanford's money.

Up to then the device had been known as the "thing" and the "can". A respectable name was needed. "Tron" was a common suffix for a vacuum tube and "klyso" was chosen as representing the bunching of waves on a beach, hence klystron.

Further detailed development work was needed. Instead of just three men (Russell, Sigurd and Bill Hansen) a whole team was now involved and a lot more effort and money was needed. Sperry Gyroscope agreed to fund the work with up to $25 000 a year. Suddenly it was big business.

The relationship with Sperry, industrial production and war-time use of klystrons are stories in themselves. The brothers were not cut out to accept direction of their ideas and their work from others¹⁷ and the relationship with their new employer involved several conflicts. Facilities were moved from California to the East Coast. Russell was engrossed in the vital patent applications and Sigurd's approach to his work brought more tuberculosis and wrote him off ¹⁸ for almost another year. At one stage, it was rumoured that Sperry wanted to buy the patents and sack the pair of them. It is not surprising that the brothers and their friends laid plans for their own post-war research laboratory.

In mid-1946 Russell returned to Palo Alto, depressed by the failure of his five-year-old marriage. But things were about to improve. He took great joy from hiking and camping and in 1946 he married a fellow camper, Dorothy. This marriage lasted until his death in the great outdoors of Alaska on July 28,1959.

The time had come for the long-discussed laboratory to become a reality. Russell found a suitable building measuring 30 by 40 feet on an unpaved street in San Carlos. It was cheap. On April 20, 1948, Varian Associates became a legal reality. Sigurd arrived in May full of energy and enthusiasm. A sum of about $45 000 was needed of which the partners could contribute only $23 000. A new recruit added $5000 but that still left them $17 000 short. Their distrust for big business ruled out going to financiers and it was Bill Hansen who once again stepped in to help¹⁹. Hansen was then a sick man and would not live another year, but he provided the remaining money, possibly by mortgaging his house. Varian Associates was established.

Honours came their way, including medals from the Franklin Institute and an honorary doctorate for Russell, who had been denied the chance to work for one. Sigurd continued to be plagued by poor health and in later years he spent more and more time in semi-retirement at his home in Mexico, building a workshop and inventing.

On 18 October, 1961, he was flying parts for his workshop back to his Mexican home. It was dark and the airport lights were out. He decided to land on the beach, crashed and was killed. It was probably the way the great adventurer would have wanted to go ²⁰.

Task I

Speak about Varian family and childhood of Russell and Sigurd.

Task II

Tell the history of klystron invention.

Task III

Tell about Russell’s life and research..

Task IV

Tell about Sigurd Varian.