The transformer mounting brackets were all replaced with steel stock twice as thick.
Add a bit of flat black paint for the OEM look.
Unfortunately while working on the transformer, I noticed the load capacitor shaft is slightly bent. The shaft seems to be brass so the real challenge is to bend it back with some precision.
Before I tore it down to work on the transformer, a quick test with high voltage probes was done on 20M to see what the voltage at the plates looked like compared to that after the pi network into the dummy load. The yellow trace is the Vpp across the 50 ohm dummy load. The blue trace is the Vpp at the plates of the four tubes ( 6LQ6’s ).
Using P = ( V**2 )/R for the output power yields P = (( 180/2.828 ) ** 2 )/50 = 81 watts into the dummy load. Then Rp = ( V **2 )/P yields Rp = (( 1060/2.828 ) ** 2 )/81 = 1,734 ohm. This looks about right for four tubes.
where 2.828 = 2 * sqrt( 2 ).
Barney Oliver
Fate works in strange ways. Although I did not work with Barney Oliver on SETI, the work on the National Science Foundation grant resulted in my landing only two buildings over from Barney Oliver's office in Bldg 2U.
The last time I saw Barney Oliver was at the end of 1979 two years before his retirement. He was having a rough time. He had led HP Labs into a program which if it had been successful could have changed Silicon Valley. I sometimes visited the Labs where I met one of the project managers for that program. They were up against fundamental issues that could not be overcome. In the end, the program was written off as a $100M loss. Barney Oliver survived it but it probably would have ended badly for a lessor person. He was definitely a visionary person willing to take substantial risk for which he deserves to be celebrated. There are many stories like this in Silicon Valley but we usually only hear the ones that turn out well. There is a similar story that happened to a professor at Stanford.
