AN/URT-3 Restoration Project - RF amplifier

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Restoration Progress pages

Acquired 3/19/2008 - a 500 watt, 136 tube, autotune HF AM/CW/FSK transmitter
Page 1 - initial cleanup - see below
Page 2 - deeper into the guts of the RFA

RFA - RF amplifier - 4-400 PA output driven by 5933 IPA (ruggedized 807)
50 ohm output - antenna matching is handled by external tuner

RFA front panel	top view 4-400 chimney upper left	vacuum variables HF tank coils below	PA autotune drive motor for vacuum variables and MF coil slugs
meters and bandswitch drive motor	left side - big slug-tuned MF coils	output RF sensor and internal dummy load	uh-oh - removed the bottom cover
HF tank coil nest	HF tank coils after cleaning	more mouse nest- this time stuffed into the autotune sequencer control relays and switches
		only a little corrosion on gears - not serious
	microswitch that steers output to internal dummy load or external antenna	driver (IPA) side - motor tuned IPA input and output cap
IPA RF sensor, autotune motor, and switch cams			crack in vacuum variable?
after an hour of vacuuming and air hose work, there was still stuff coming out of the autotune sequencer	epoxy? pieces that fell out when cleaning