Pprat, thanx for the trip down memory lane. That machine came out in 1977, the year before Whites introduced their first motion discriminators (original 6000, then the 6db, etc...).
UK Brian hits the nail on the head in everything he said. The only thing I'll add, is I remember when we first started to see a guy swinging a Red Baron, and then the 6000s. We thought they were nuts, because of their
obvious lack of know-how on the proper way to swing. You see, for the earlier all-metal TRs, then the VLF all-metal and TR disc, it was just
assumed that you needed to go slow and pay attention to whispers, etc..... Imagine what it looked like to see someone going along like they were practicing their golf swings! But believe me, we stopped "laughing" when we saw the silver these guys were bringing in to the club meetings

Within a few years, there wasn't anyone who didn't have a motion discriminator of some brand or another
