Winter 2008 Issue

The Lost Letters of KH6UK
Part 3: The Klystron Years

In part 1 of this series WA2VVA discussed how he came across the lost letters of Tommy Thomas, KH6UK, along with Tommy’s tropo QSO with W6NLZ. In part 2 he discussed Tommy’s pioneering VHF EME activities. Here WA2VVA presents the effect that the Klystron had on Tommy’s EME activities.

By Mark Morrison, WA2VVA

Photo A. The Eimac KW Klystron delivered to W2CXY in 1960.

After three months of vacation, Tommy Thompson, KH6UK, and Helyne were back in Kahuku by February of 1960. Tommy’s first job was to prepare for 432 Mc tropo tests with John and the other West Coast hams. In prior years, Tommy would have already been prepared for the next inversion season, but his long-deserved vacation took priority. Tommy had this to say:

The 4 long johns are sitting in the yard waiting for phasing lines and matching xfrmrs. Shouldn’t take long once I get the bridge. The 432 gang is all set up and we should be ready to start tests with NLZ in a week or two now.

It was about this time when Walt Morrison, W2CXY, was well on his way to building the first 1296 Klystron moonbounce station in the state of New Jersey, and one of only three anywhere in the world (the other two being W6HB in California and W1FZJ in Massachusetts). In January of 1960, Eimac shipped Walt the 3K2500LX Klystron shown in photos A and B. This historic tube and original shipping crate are now part of the Infoage Technology Museum in Wall, New Jersey.
Walt’s interest in 1296 Mc made Tommy think about the band, even though his hands were already full on 144 and 432 Mc:

The reason I mentioned 1296 Mc to Carl (W2AZL) was that I know just what will happen when and if John and I are lucky enough to get across on 432 Mc—that guy NLZ won’t let one rest until we try it on 1296 too!

Apparently, Tommy was doing more than thinking about the band, because he later wrote that a dish was coming his way. It might be possible that Tommy’s visit to Washington, DC the year before had opened the door to some surplus dishes. Walt received the 15-foot dish shown in photo C from the US Air Force, and it is believed to have been manufactured by the General Bronze Corporation of Long Island, New York. Tommy’s dish was probably surplus equipment from somewhere on the island. Considering this was only 1960, both dishes probably had seen radar or early satellite tracking duty.
Regarding the dish. Latest word is that a 28 footer is on its way and should arrive some time in March. It is just a Kennedy dish—no dipole, no mntg. Don’t know just what I will do with it yet as it has no particular advantage over the Yagi array.

Although Tommy showed an interest in 1296, he wasn’t thinking moonbounce at this time. Rather, he was more interested in 1296 for continued trans-pacific work with John Chambers, W6NLZ.

Apparently the boys back there are serious about doing the m/b [moonbounce] job on 1296. More power to them. They will need it. I think it is going to take some doing even on 144 Mc. Maybe the extra antenna gain on 1296 will do the trick; time will tell.
As Walt was busy putting his Klystron power supplies together, he apparently contemplated one more shot at 2-meter moonbounce. Tommy commented on this in one of his letters:

I see you are now talking 42 foot Yagis with 21/2 inch and 2 inch phase shift. Boy, that is going to be a big hunk of stuff to get up in the air—and keep up! Think I would settle for four 36 footers. As I recall Ross [Bateman] had to go to stacked rhombics before he got any results worthwhile. I agree entirely with Ross—every step has to be checked and double checked to make sure you are actually getting the gain, etc., you are suppose to. The tape of Ross’s moonbounce signal was very interesting and should be able to be duplicated by a couple of serious guys. I wonder just how much gain was picked up by ground reflection. Evidently some as Ross claimed signal was best with ant aimed about 2° above the horizon. Has anyone heard their own echo overhead?

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