The Yaesu FTDX-100 is a 1960s-era amateur-band transceiver, of hybrid design - primarily solid-state, but 3 tubes for the transmitter driver and output. It's compact, solidly built, and well-featured:

• 80, 40, 20, 15, 10M band coverage
• SSB, CW, AM
• crystal calibrator
• varactor-tuned tweaking of the VFO for fine adjustment and offsetting the T/R frequencies
• VOX
• inverter power supply for mobile operation from 12VDC in addition to 100-240VAC line voltage

The downside to the compactness is difficulty of serviceability. Typical of Japanese construction of the era, the compactness was achieved by a layered construction that makes access to many components difficult.

The schematic linked below is a redrawing of the manufacturer schematic to make some sense out of it.

SUB-PAGES: Yaesu FTDX-100 Schematic (pdf) in new window Unit Log

EXTERNAL LINKS & REFERENCES: The FTDX-100 at Fox Tango International

Photos

Front.	Rear.
Top.	Bottom. Note removing the front bezel helps with access to some of the componentry.
VFO opened top.	VFO opened bottom.
Side-band oscillators compartment.	Fixed-channel board.