Miscellaneous Electronic Reports, Data, Historical Items, Projects
Repair of ICOM IC-28A, -28H squelch pot plus battery replacement

A three-page report on replacing the squelch pot in this older Icom 2-meter FM radio. If yours is bad this is how to fix it. This is a good, rugged radio well worth fixing if possible. Icom will not repair this radio since it is an older model.

Repair of probes for the HP 8405A Vector Voltmeter

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.  Note added April 2016 (see last page of document)

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

Measurement of Complex Impedance - HP App Note 77-3, April 1967.  Discribes use of the HP4815A and HP8405A instruments to measure complex impedance.

James Millen Co. 1972 catalog - pdf file, 12 Meg

Sierra Electonic Co. catalog, possibly early 70's - pdf file, 18 Meg

Bird Model 43 Manual, not dated, but possibly from the 1960's. - pdf file, 13 Meg

Daiwa NS-660 series SWR and Power Meters, manual, pdf file

Eimac Y-870, A High-mu Power Triode, pdf file

Collins Mechanical Filters Catalog, from 1970, pdf file, 15 Meg

Cornell-Dubilier, HAM-M Antenna Rotator, copy of manual, pdf file, 12 Meg

This is an older rotator now built by Hy-Gain. Similar to Model IV.

Vectron Model 218-9474, Crystal Oscillator, data sheet and specifications, pdf file

Photos of above Vectron Oscillator, Vectron_1, Vectron_2 This unit may have been used in a
Rockland Frequency Synthesizer.

"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.