From the Silver Pioneer Website
TX-6700
The TX-6700 was offered by Pioneer between 1978 and 1980, according to one source, but another source says it was manufactured earlier than this because it did not have the family resemblance of other tuners in the Pioneer line in the late 1970s. The reason for this is the location of the signal strength and stereo signal meters on the front panel instead of the tuning dial area. Price was $180.00.