Yet more Horrors in the fusion story.
Posted: Mon Aug 27, 2007 5:26 pm
Steve Blasing and I chatted the other night as I was getting my facts in line and rechecking some data related to the ITT effort.
Steve is a d-mned good tech and knows his stuff. Now in his late seventies, his memory is almost as sharp as Genes was on specific events.
Steve and I chatted about the electron multipaction method and its abortive result. Steve told me something I never knew even though the perfesser and I sat down with he and Gene a few year ago in Fort Wayne for a full day long interview.
Steve said that so far as he was concerned the actual workability story on the Farnsworth electron multipactor concept was not really in! As he went into the technical elaboration for this bizarre statement, I realized he might just be right, at least as far as good data gathering went during the tests.
I seems that in those early days when Farnsworth was working with the top hat system, (bell jar, solid hollowed dynode), they looked to a capacitive coupled, choke blocked, modulated HV using a 1-2KW RF amp driven by a generator that could go up to 800mhz for attaining the multipactor mode.
Steve came on as a part time, inter-departmental "share, as needed", tech right at the tail end of the Mark I system. He, said that he was specifically brought in to help with the great difficulties they were having with the RF gear. He said he was floored to see what was happening. He yelled to me that "there was no match" and no way to match the system at all frequencies and no one had a clue!
Apparently, there was a long encased and encapsulated capacitor used for coupling that no member of the team knew the value of, nor did they know the value of the choke. (also entombed in the guts of the device).
No one would allow the device to be taken apart as the ITT people were coming for the grand inspection and they did not want to take it apart with the associated issues involved with re-bakeout and possible damage of the now working system.
Steve said that he assembled an incident and reflected power hook up and tweaked the system as best he could at the frequency they were interested in at that moment. He noted that after he did this, they never bothered to readjust in any future test and he was constantly having to repair the power amp which cooked due to mismatch or the RG-9 cable that fried several times due to a voltage node or reflection. He was always called only after a disaster to clean up.
Thus, as Farnsworth envisioned electron multipaction in the system, it may never have been optimally tested!!! GEEZ Louise! Or as Steve said, "Garsh, those guys just didn't have a clue!"
His efforts ultimately were recognized by Farnsworth, who tended to recognize talent. But it was only after they switched over to ion based fusors that Steve was called upon to work full half days on loan as an actual part of the fusion effort. Ultimately, in late 1963, he was yanked or transfered permanently to the fusor team as the techical aide to the just hired, Bob Hirsch.
So was electron multipaction and the super virtual cathode viable? Maybe not, but it looks as if the original fusor team did not do the job to a level that Farnsworth perhaps envisioned.
Oh well, more sadness.
Richard Hull
Steve is a d-mned good tech and knows his stuff. Now in his late seventies, his memory is almost as sharp as Genes was on specific events.
Steve and I chatted about the electron multipaction method and its abortive result. Steve told me something I never knew even though the perfesser and I sat down with he and Gene a few year ago in Fort Wayne for a full day long interview.
Steve said that so far as he was concerned the actual workability story on the Farnsworth electron multipactor concept was not really in! As he went into the technical elaboration for this bizarre statement, I realized he might just be right, at least as far as good data gathering went during the tests.
I seems that in those early days when Farnsworth was working with the top hat system, (bell jar, solid hollowed dynode), they looked to a capacitive coupled, choke blocked, modulated HV using a 1-2KW RF amp driven by a generator that could go up to 800mhz for attaining the multipactor mode.
Steve came on as a part time, inter-departmental "share, as needed", tech right at the tail end of the Mark I system. He, said that he was specifically brought in to help with the great difficulties they were having with the RF gear. He said he was floored to see what was happening. He yelled to me that "there was no match" and no way to match the system at all frequencies and no one had a clue!
Apparently, there was a long encased and encapsulated capacitor used for coupling that no member of the team knew the value of, nor did they know the value of the choke. (also entombed in the guts of the device).
No one would allow the device to be taken apart as the ITT people were coming for the grand inspection and they did not want to take it apart with the associated issues involved with re-bakeout and possible damage of the now working system.
Steve said that he assembled an incident and reflected power hook up and tweaked the system as best he could at the frequency they were interested in at that moment. He noted that after he did this, they never bothered to readjust in any future test and he was constantly having to repair the power amp which cooked due to mismatch or the RG-9 cable that fried several times due to a voltage node or reflection. He was always called only after a disaster to clean up.
Thus, as Farnsworth envisioned electron multipaction in the system, it may never have been optimally tested!!! GEEZ Louise! Or as Steve said, "Garsh, those guys just didn't have a clue!"
His efforts ultimately were recognized by Farnsworth, who tended to recognize talent. But it was only after they switched over to ion based fusors that Steve was called upon to work full half days on loan as an actual part of the fusion effort. Ultimately, in late 1963, he was yanked or transfered permanently to the fusor team as the techical aide to the just hired, Bob Hirsch.
So was electron multipaction and the super virtual cathode viable? Maybe not, but it looks as if the original fusor team did not do the job to a level that Farnsworth perhaps envisioned.
Oh well, more sadness.
Richard Hull