This four-page report details the repairs I made on a burned out probe. I replaced two diodes and one P-Channel FET in the probe.

HP8405A Technical Data - six page summary of instrument, Jan. 1977, pdf file, 5650 KB

James Millen Co. 1972 catalog - pdf file, 12,151 KB

"Extra Terrestrial Relays" by Arthur C. Clarke, from Wireless World, October, 1945.

An amazing article which describes how geostationary statellites could be used to relay radio
communcations around the globe. Mr. Clarke was far ahead of his time. This technology was
not able to be put into place until decades later. The geostationary orbit is now called The Clarke
Belt in his honor.