The 767GX is an excellent rig that far surpasses today's "introductory" rigs in most ways. It does not outperform today's "high end" rigs, though; but in its time, it was a "high end" rig.
It's packed with a lot of features that worked well, one being an internal AC power supply. It has an internal automatic antenna tuner and works all of our HF bands except 60 meters, since that was activated for use years after the rig was designed and sold. It was discontinued in about 1990 as I recall.
It's very versatile in that you can add VHF-UHF modules to increase its band coverage and many out there have the 2m and 70cm modules installed. Then, some don't.
It had good modulation, good keying characteristics, is digital mode compatible and has a CAT interface for computer control -- that was a very "new" feature in those days, one that most rigs that vintage do not have.
The only "issues" I can recall hearing about were VHF-UHF modules failing and the main tuning encoder sometimes failing. The tuning encoder can be replaced and it's not expensive; I have no idea how much it might cost to repair the VHF-UHF modules but if you're only concerned with HF operation then this wouldn't really matter.
BTW even if the tuning encoder fails completely, you can still use the rig by using the "up" and "down" buttons which are on the rig and also on the matching microphone and allow you to tune around electronically without a knob. But the knob is nicer.
I'd guess one in perfect, operational condition is worth about $750 or so. Because the rig is guaranteed to be at least 20 years old (and possibly 25, since it was introduced in 1986), I would absolutely never buy one "sight unseen." I'd want a demonstration and a chance to use it for a few minutes prior to exchanging cash for hardware, unless the seller can offer a written warranty (AES does this with used/reconditioned gear, and some other dealers might also).
It's quite a nice rig, about equivalent to an FT-950 or similar today.
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