Sansui has an excellent reputation when it comes to the Tuners they made. Models like the TU-9900 and TU-717 are very popular (as you can see from the bidding & prices on Ebay), and other models bring in even more $$, such as the TU-919 and the ultimate- the Sansui TU-X1.
Mid 70's models like the TU-7700 should be quite excellent in my opinion, so I wouldnt have too many doubts to buy one if the price was reasonable. If youre interested in it, I suggest contacting the seller beforehand to provide more photos- of the inside, and back of the unit as well (unless he was generous in that regard already with what he mightve posted in the Ebay auction). Also ask what shipping price to your location would be- and from this, you can get a better idea of what the seller is like by his reply to you (though if he has a perfect Feedback record, he's likely to be ok- but never hurts to check beforehand with the seller) - Also ask (if not mentioned in the auction description, if he's the original owner and whatever background history he can provide on the tuner- whether it has ever had any problems/repairs to the best of his knowledge) Having the original operating manual is a plus- people who manage to keep the manuals after ~ 30 years, usually indicates a person who looks after their things.
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